The following pairs are correct:- cyanide, [tex]CN^-[/tex],- chlorate, [tex]ClO^{-3[/tex],- nitrate, [tex]NO^{-3[/tex].Therefore, the correct answers are cyanide, [tex]CN^-[/tex]; chlorate, [tex]ClO^{-3[/tex]; and nitrate,[tex]NO^{-3[/tex] .
Cyanide is a polyatomic ion consisting of a carbon atom and a nitrogen atom that is triple-bonded to each other, with a negative charge on the ion. The formula for cyanide is [tex]CN^-[/tex].
Chlorate is a polyatomic ion consisting of a chlorine atom and three oxygen atoms, with a negative charge on the ion. The formula for chlorate is [tex]ClO^{-3[/tex].
Nitrate is a polyatomic ion consisting of a nitrogen atom and three oxygen atoms, with a negative charge on the ion. The formula for nitrate is [tex]NO^{-3[/tex].
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he density of a 20.3 m ch3 oh (methanol) solution is 0.858 g/ml. what is the molality of this solution? h2 o is the solvent.
The molality of this solution is equal to 97.41 m.
How to determine the molality of this solution?In order to determine or calculate the molality of this solution, we would have to determine the mass of the solution.
In Chemistry, the molality of a chemical solution can be determined or calculated by using the following mathematical equation (formula);
Molality = mol. of solute/weight of solvent (kg)
For the mass of solution, we have the following:
Mass of solution = 0.858 g/ml × 1000
Mass of solution = 858 g.
Mass of solution = mass of solute + weight of solvent
858 = (20.3 × 32) + weight of solvent
Weight of solvent = 858 - 649.6
Weight of solvent = 208.4
Molality = 20.3/208.4 × 1000
Molality = 97.41 m.
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most acid waves used in salons have a ph value between _____.
Most acid waves used in salons have a pH value between 4.5 and 7.0. The pH value of an acid wave determines its strength and the degree of curl that can be achieved on the hair.
A lower pH value indicates a stronger acid and a tighter curl, while a higher pH value indicates a weaker acid and a looser curl. Acid waves are typically milder than alkaline waves, which have a pH value of around 9.0-9.6 and are less damaging to the hair.
It is important to choose the right strength of acid wave based on the type and condition of the hair. Fine or damaged hair requires a milder acid wave, while coarse or resistant hair requires a stronger one. Acid waves are typically left on the hair for a shorter period of time than alkaline waves, which reduces the risk of overprocessing and damage to the hair.
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what do you know about reversible reactions and equilibrium of reversible reactions? write an equation to demonstrate reversible reaction
We can see a reaction that does depict an equilibrium situation in the equation;
A + B ⇔ C + D
What is the equilibrium reaction?Reversible reactions are those that happen chemically and can go either forward or backward, i.e., reactants can become products and products can become reactants.
The reaction system reaches equilibrium when the rate of the forward reaction equals the rate of the reverse reaction. There is no more change in the system at this stage, and the concentrations of the reactants and products stay constant over time.
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write a net ionic equation to show that dimethylamine, (ch3)2nh behaves as a bronsted-lowry base in water.
The reaction as follows,
(CH₃)₂NH (aq) + H₂O (aq) ------------> (CH₃)₂NH₂⁺ (aq) + OH⁻ (aq)
The net ionic equation will be,
(CH₃)₂NH (aq) + H⁺(aq) ---------> (CH₃)₂NH₂⁺ (aq)
Bronsted-Lowry base are proton acceptor, so (CH₃)₂NH is a base as, it accepts proton to form (CH₃)₂NH . A Brønsted-Lowry base is any species that is capable of accepting a proton, which requires a lone pair of electrons to bond to the H⁺ . Water is amphoteric, which means it can act as both a Brønsted-Lowry acid and a Brønsted-Lowry base.
The net ionic equation will be,
(CH₃)₂NH (aq) + H⁺(aq) ---------> (CH₃)₂NH₂⁺ (aq)
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give a reason why it is necessary to dispose off chemicals already used
when positron emission takes place . question 6 options: the atom is destroyed a neutron changes into an electron and a positron a proton changes into a neutron a neutron changes into a proto
When positron emission takes place, a neutron changes into a proton and a positron.
What is this emissionPositron emission is a type of radioactive decay in which a proton-rich nucleus in an atom undergoes a transformation that changes one of its neutrons into a proton and a positively charged particle called a positron. The newly created proton remains in the nucleus, while the positron is emitted from the atom.
The overall effect of positron emission is to decrease the number of neutrons in the nucleus and increase the number of protons, resulting in a different element.
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calculate the pH of this solution: Buffer 2: 50.0 mL of 0.18 M NH3 with 5.0 mL of 0.36 M HBr.
The pH of the buffer solution is approximately 9.425.
To calculate the pH of the buffer solution, consider the acid-base equilibrium between NH₃ (ammonia) and its conjugate acid, NH₄⁺ (ammonium), as well as the addition of HBr (hydrobromic acid).
First, calculate the moles of NH₃ and NH₄⁺ in the solution:
Moles of NH₃ = Volume (L) x Concentration (mol/L)
Moles of NH₃ = 0.050 L x 0.18 mol/L
Moles of NH₃ = 0.009 mol
Since NH₃ and NH₄⁺ are in a 1:1 ratio in the buffer solution, the moles of NH₄⁺ is also 0.009 mol.
Next, calculate the moles of HBr:
Moles of HBr = Volume (L) x Concentration (mol/L)
Moles of HBr = 0.005 L x 0.36 mol/L
Moles of HBr = 0.0018 mol
To determine the resulting concentrations of NH₃ and NH₄⁺ in the buffer solution, consider the changes in moles after the addition of HBr:
Moles of NH₃ in the buffer = Initial moles of NH₃ - Moles of HBr
Moles of NH₃ in the buffer = 0.009 mol - 0.0018 mol
Moles of NH₃ in the buffer = 0.0072 mol
Moles of NH₄⁺ in the buffer = Initial moles of NH₄⁺ + Moles of HBr
Moles of NH₄⁺ in the buffer = 0.009 mol + 0.0018 mol
Moles of NH₄⁺ in the buffer = 0.0108 mol
Calculate the concentrations of NH₃ and NH₄⁺ in the buffer solution:
Concentration of NH₃ in the buffer = Moles of NH₃ / Volume of buffer (L)
Concentration of NH₃ in the buffer = 0.0072 mol / 0.055 L
Concentration of NH₃ in the buffer = 0.131 mol/L
Concentration of NH₄⁺ in the buffer = Moles of NH₄⁺ / Volume of buffer (L)
Concentration of NH₄⁺ in the buffer = 0.0108 mol / 0.055 L
Concentration of NH₄⁺ in the buffer = 0.196 mol/L
Finally, we can calculate the pH of the buffer using the Henderson-Hasselbalch equation:
pH = pKa + log([A-]/[HA])
The pKa for the NH₃/NH₄⁺ system is approximately 9.25 at 25°C.
pH = 9.25 + log(0.196/0.131)
pH = 9.25 + log(1.496)
pH = 9.25 + 0.175
pH ≈ 9.425
Therefore, the pH of the buffer solution is approximately 9.425
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the main cause of the increase in the amount of co2 in earth's atmosphere over the past 150 years is
The main cause of the increase in the amount of CO2 in the Earth's atmosphere over the past 150 years is human activities, particularly the burning of fossil fuels such as coal, oil, and natural gas for energy and transportation.
Other human activities that contribute to CO2 emissions include deforestation and industrial processes. These emissions have resulted in a significant increase in the concentration of CO2 in the atmosphere, leading to climate change and global warming.
The main cause of the increase in the amount of CO2 in Earth's atmosphere over the past 150 years is the burning of fossil fuels, such as coal, oil, and natural gas, for energy production and transportation. This process releases large quantities of carbon dioxide, contributing to the greenhouse effect and global warming.
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calculate the molality of a 5.41 m aqueous mgbr2 solution with a density of 1.52 g/ml.
The molality of the 5.41 m aqueous MgBr2 solution with a density of 1.52 g/ml is 3.58 m/kg.
In this case, the solute is MgBr2, and the solvent is water. The given concentration of the solution is 5.41 m, which means there are 5.41 moles of MgBr2 per liter of solution.
To calculate the molality, we need to convert the given concentration into moles of solute per kilogram of solvent. We can do this using the density of the solution, which is given as 1.52 g/ml.
First, we need to calculate the mass of 1 liter of the solution. This can be done using the density:
Mass = volume x density
Mass = 1 L x 1.52 g/ml
Mass = 1.52 kg
Now we know that 1 liter of the solution has a mass of 1.52 kg. To calculate the mass of solvent in the solution, we need to subtract the mass of the solute:
Mass of solvent = Mass of solution - Mass of solute
We can calculate the mass of solute using the concentration:
5.41 mol MgBr2 / 1 L solution x 1.52 kg solution / 1000 mL solution = 0.00822 kg MgBr2
Mass of solvent = 1.52 kg - 0.00822 kg
Mass of solvent = 1.51178 kg
Now we can calculate the molality:
Molality = moles of solute / mass of solvent (in kg)
Molality = 5.41 mol / 1.51178 kg
Molality = 3.58 m/kg
Therefore, the molality of the 5.41 m aqueous MgBr2 solution with a density of 1.52 g/ml is 3.58 m/kg.
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What is the total number of outer (valence) electrons in nitrogen dioxide, NO2? a. 5 b. 6 c. 7 d. 8
The total number of outer (valence) electrons in [tex]NO_2[/tex] is the sum of the lone pairs and the shared electrons, which is 5 + 4 + 4 = 13. Thus, the correct answer is option C: 7.
The total number of outer (valence) electrons in nitrogen dioxide ([tex]NO_2[/tex]) can be determined by examining the Lewis structure of the molecule. Nitrogen (N) has five valence electrons, and each oxygen (O) has six valence electrons. The molecule consists of one nitrogen atom and two oxygen atoms, so the total number of valence electrons in [tex]NO_2[/tex] is 5 + 2(6) = 17. To find the number of outer (valence) electrons in the molecule, we need to consider the number of electrons that are shared between the atoms and the number of lone pairs of electrons. In [tex]NO_2[/tex], the nitrogen atom shares two electrons with each of the oxygen atoms to form two covalent bonds.
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How do you exhibit a gas for others especially during the holy week and this time of pandemic? Make a reflection paper
Reflecting on Exhibiting a Gas during the Holy Week amidst the Pandemic.
In the midst of the Holy Week and the ongoing pandemic, finding ways to exhibit a gas to others can be challenging. Typically, gas exhibits involve gathering people nearby, which is not advisable during this time of public health crisis. This reflection paper explores alternative approaches and reflects on the significance of adapting and finding new ways to share knowledge and experiences related to gases, considering the unique circumstances we currently face. Embracing Virtual Platforms: One way to exhibit a gas during the Holy Week, especially in the context of the pandemic, is to leverage virtual platforms. With advancements in technology, we can use video conferencing tools or online platforms to conduct virtual demonstrations or presentations about gases. These platforms allow us to share knowledge, experiments, and educational materials with others while maintaining social distancing and prioritizing safety.
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portionpac chemical's dedication to its customers, employees, and the environment is an example of:
PortionPac Chemical's dedication to its customers, employees, and the environment is an example of corporate social responsibility (CSR). CSR refers to a company's responsibility towards its stakeholders, including customers, employees, shareholders, suppliers, and the environment.
PortionPac Chemical's commitment to its customers is evident through its high-quality products and exceptional customer service. The company ensures that its products are safe, effective, and easy to use, and it offers training and support to help its customers achieve the best results.
PortionPac Chemical also values its employees and strives to provide a safe and inclusive workplace where employees can grow and thrive. The company invests in employee training and development, offers competitive wages and benefits, and fosters a culture of respect and teamwork.
Moreover, PortionPac Chemical is committed to protecting the environment and reducing its carbon footprint. The company uses sustainable manufacturing practices, reduces waste and emissions, and develops eco-friendly products that are safe for people and the planet.
Overall, PortionPac Chemical's dedication to CSR demonstrates its commitment to creating long-term value for its stakeholders while making a positive impact on society and the environment.
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Explain why the rates of diffusion and effusion, for any particular gas at constant temperature, are proportional to the square root of the molar mass of the gas
The rates of diffusion and effusion of gases are described by Graham's law of effusion/diffusion.
According to Graham's law, the rate of diffusion or effusion of a gas is inversely proportional to the square root of its molar mass. This relationship can be explained by considering the kinetic theory of gases. The kinetic theory of gases states that gases consist of particles (atoms or molecules) that are in constant random motion. When two gases are at the same temperature, they have the same average kinetic energy. However, individual gas particles can have different speeds and kinetic energies based on their masses. Now, let's consider the process of diffusion, which is the movement of gas particles from an area of higher concentration to an area of lower concentration. In diffusion, gas particles move randomly and collide with each other. The lighter particles, due to their higher speeds, will cover a larger distance in a given time compared to heavier particles.
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the tendency of a mineral to break and produce smooth, curving, shell-shaped surfaces is termed:
The tendency of a mineral to break and produce smooth, curving, shell-shaped surfaces is termed "conchoidal fracture." This characteristic is observed in certain minerals due to their specific atomic structure and bonding patterns. Minerals with this property exhibit a predictable breakage pattern, creating distinctive curving surfaces that resemble the shape of a seashell or a conch.
Conchoidal fracture is commonly seen in minerals with strong covalent or ionic bonds, such as quartz and obsidian. These minerals lack distinct cleavage planes, so when they break, they tend to form these smooth, curved surfaces. The absence of cleavage planes is a result of the uniform distribution of bonds throughout the mineral, which causes them to fracture in a more random manner, creating the curving shape.
In summary, the term "conchoidal fracture" refers to the tendency of a mineral to break and produce smooth, curving, shell-shaped surfaces. This property is observed in minerals with strong covalent or ionic bonds and a lack of distinct cleavage planes, such as quartz and obsidian. The unique breakage pattern is due to the uniform distribution of bonds within the mineral's structure, resulting in a random, curved fracture pattern.
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in order to know the current rules regarding chemical sanitizers, the manager should check
In order to know the current rules regarding chemical sanitizers, the manager should check with their local health department and review the regulations outlined in the Food Code.
They should also consult with the manufacturer's instructions for the specific chemical sanitizer being used to ensure proper dilution and application methods are being followed.
The Food Code is a set of guidelines for food safety that is published by the United States Food and Drug Administration (FDA). It is designed to help regulate the handling, preparation, and storage of food in restaurants, grocery stores, and other food establishments.
The Food Code contains best practices and recommendations for food safety, such as proper cooking temperatures, hygiene practices, and guidelines for preventing cross-contamination. It also includes guidelines for food service equipment, facility design, and employee training.
The Food Code is updated periodically to reflect the latest scientific research and best practices in food safety. Many states in the United States have adopted the Food Code as part of their own food safety regulations, while others have developed their own guidelines based on the principles of the Food Code.
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what charge would be needed on f2 to generate an ion with a bond order of 2
The charge needed on F2 to generate an ion with a bond order of 2 is -1.
The bond order is the number of chemical bonds between two atoms. For F2, the bond order is 1 because there is one bond between the two fluorine atoms. To generate an ion with a bond order of 2, we need to remove one electron from F2 to form F2+ with a bond order of 1.5, and then remove another electron from F2+ to form F2 2- with a bond order of 2. However, we cannot remove two electrons from a neutral molecule without introducing a charge.
Therefore, we need to remove one electron from F2, which requires a charge of -1 to form F2-.
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a) which elisa type was used in the experiments above? why? (hint: think about what we are trying to detect.) b) what was/were the likely positive control(s) used in the three experiments? can we use the same positive control for all three elisas? (h
ELISA (enzyme-linked immunosorbent assay) is a commonly used technique in immunology to detect the presence of specific antibodies or antigens in a sample.
The technique involves immobilizing the antigen or antibody of interest onto a surface, and then detecting it using a specific enzyme-linked antibody or antigen.
a) The type of ELISA used in the experiment would depend on the specific antigen or antibody being detected. If the antigen or antibody is present in low concentrations, a direct ELISA may be used, where the antigen or antibody is directly immobilized onto the surface and then detected using a specific enzyme-linked antibody or antigen.
Alternatively, an indirect ELISA may be used, where the antigen or antibody is first immobilized onto the surface using a non-specific antibody, and then detected using a specific enzyme-linked antibody or antigen. The choice of ELISA type would depend on the sensitivity and specificity required for the experiment.
b) The positive control used in the three experiments would depend on the antigen or antibody being detected. A positive control is a known sample that contains the antigen or antibody of interest, and is used to ensure that the assay is working correctly.
The positive control should have a high concentration of the antigen or antibody, and should be tested in the same conditions as the experimental samples.
It is possible to use the same positive control for all three ELISAs if the antigen or antibody being detected is the same. However, if the antigen or antibody is different, then a different positive control would be required for each assay.
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if the vapor pressure of water had not been taken into account, what would have been the calculated value of r?
If the vapor pressure of water had not been taken. An evaluation of R was performed, following the procedure described in this module.
Vapour pressure is a degree of the tendency of a cloth to alternate into the gaseous or vapour state, and it will increase with temperature. The temperature at which the vapour strain on the floor of a liquid. The barometric strain changed into 736 torr, the temperature changed into 295k and quantity of hydrogen fueloline accrued changed into 35.6 mL. The calculated cost of R changed into 82.1 mL atm K-1 mol-1. As the temperature of a liquid or solid increases its vapour pressure also increases. Alternatively, vapour pressure decreases as the temperature decreases.
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a sample of an unknown isotope decays according to the figure. what is the half-life?
In order to determine the half-life of an unknown isotope, we need to examine its decay curve. The half-life of an isotope is the amount of time it takes for half of the sample to decay.
We can see that the initial activity is 100%. After one half-life has passed, the move has decreased to 50%. After another half-life, the action is 25%. After a third half-life, the movement is 12.5%, and so on. To find the half-life, we need to determine how much time it takes for the activity to decrease to half its initial value. In this case, we can see that the activity decreases from 100% to 50% after one half-life has passed.
Therefore, the half-life of the unknown isotope is the time it takes for one-half of the sample to decay, which is equal to the time it takes for the activity to decrease to half of its initial value. From the figure, we can estimate that the half-life is approximately 3 hours. In summary, the half-life of the unknown isotope is the time it takes for half of the sample to decay, and in this case, it appears to be approximately 3 hours.
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Forensic scientists play a large role in keeping the community safe and spreading justice. They also play an active role in showing biological proof items in a crime to help investigators understand what occurred. Providing answers about a crime can provide comfort to families that the victims. This can lead to a deep sense of accomplishment and potentially to a higher rate of job satisfaction.
How can i complete the paragraph
Ensuring public safety and upholding the rule of law are major responsibilities of forensic scientists.
Ensuring public safety and upholding rule of law are significant responsibilities of forensic scientists. They actively participate in demonstrating biological evidence from a crime to aid detectives in understanding what happened. Giving victims' relatives information about a crime helps console them. This may result in a strong sense of accomplishment and work satisfaction. A sharp eye for detail and ability to analyse complicated data are additional requirements for forensic scientists.
They often collaborate and have a chance to learn from others since they work in teams with attorneys, and other professionals. The discipline of forensic science is constantly changing due to technological advancements, opening up new possibilities for development and innovation. Forensic scientists' work is crucial to preserving society's safety and well-being and can give them a sense of fulfilment in their careers.
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another metal phosphate is aluminum phosphate. it will behave similar to calcium phosphate in an acid solution, and will form an equilibrium between reactants and products. what is the net ionic equation including phases for alpo4(s) dissolving in h3o (aq) ?
The following is a representation of the net ionic equation for the dissolution of aluminium phosphate (AlPO4) in an acidic solution (H3O+):
Al3+(aq) + H2PO4-(aq) + 3H2O(l) AlPO4(s) + 4H3O+(aq)Aqueous aluminium ions (Al3+) and aqueous hydrogen phosphate ions (H2PO4-), as well as liquid water (H2O), are produced in this reaction when the solid aluminium phosphate (AlPO4) combines with the hydronium ions (H3O+) in the acidic solution.The spectator ions, or ions that do not change throughout the reaction and remain in solution in their original form, are not included in the net ionic equation, which concentrates on the species that actively engage in the process. The spectator ions in this scenario are the hydrogen phosphate and aluminium ions' counterions, which can either take the form of chloride or nitrate ions.Aqueous aluminium ions (Al3+) and aqueous hydrogen phosphate ions (H2PO4-), as well as liquid water (H2O), are produced in this reaction when the solid aluminium phosphate (AlPO4) combines with the hydronium ions (H3O+) in the acidic solution.The spectator ions, or ions that do not change throughout the reaction and remain in solution in their original form, are not included in the net ionic equation, which concentrates on the species that actively engage in the process. According to the source of the aluminium phosphate, the spectator ions in this instance are the counterions to the aluminium and hydrogen phosphate ions, which are present as chloride or nitrate ions.
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Accurately measure approximately ( within 10%)1.00g of sodium hydroxide.
Using a digital weighing scale to accurately measure approximately ( within 10%)1.00g of sodium hydroxide.
Digital weighing has a precision of at least 0.1 g. The scale is calibrated and placed on a stable surface.
Place a weighing boat or a piece of weighing paper on the scale and press the tare button to reset the scale to zero.
Using a spatula, transfer some of the sodium hydroxide pellets or powder to the weighing boat or paper until the scale reads around 1.1 g.
Using the spatula, remove small amounts of sodium hydroxide at a time until the scale reads exactly 1.0 g.
Once you have reached 1.0 g, transfer the sodium hydroxide to a clean and dry container, such as a beaker or a test tube.
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use the following data to estimate δh⁰f for potassium bromide. k(s) + 1/2 br2(g) → kbr(s)
Lattice energy −691 kJ/mol
Ionization energy for K 419 kJ/mol
Electron affinity of Br −325 kJ/mol
Bond energy of Br2 193 kJ/mol
Enthalpy of sublimation for K 90. kJ/mol
The estimated δh⁰f for potassium bromide is -314 kJ/mol. To estimate δh⁰f for potassium bromide, we can use the Hess's Law of Heat Summation, which states that the enthalpy change of a chemical reaction is independent of the pathway between the initial and final states.
The first step is the sublimation of solid potassium, which requires an input of energy and can be represented as follows:
K(s) → K(g) ΔH = +90 kJ/mol
The enthalpy change for this process is given as +90 kJ/mol.
The second step is the dissociation of gaseous bromine into bromine atoms, which also requires an input of energy and can be represented as follows:
Br2(g) → 2Br(g) ΔH = +193 kJ/mol
The enthalpy change for this process is given as +193 kJ/mol.
The third step is the ionization of gaseous potassium atoms, which requires an input of energy and can be represented as follows:
K(g) → K+(g) + e- ΔH = +419 kJ/mol
The enthalpy change for this process is given as +419 kJ/mol.
The fourth step is the electron affinity of bromine atoms, which involves the release of energy and can be represented as follows:
Br(g) + e- → Br-(g) ΔH = -325 kJ/mol
The enthalpy change for this process is given as -325 kJ/mol.
The fifth step is the formation of potassium bromide from gaseous potassium cations and bromine anions, which involves the release of energy and can be represented as follows:
K+(g) + Br-(g) → KBr(s) ΔH = -691 kJ/mol
The enthalpy change for this process is given as -691 kJ/mol.
By adding up the enthalpy changes for the five steps, we can obtain the enthalpy change for the overall reaction:
K(s) + 1/2Br2(g) → KBr(s)
ΔH = ΔH(sublimation of K) + ΔH(dissociation of Br2) + ΔH(ionization of K) + ΔH(electron affinity of Br) + ΔH(formation of KBr)
ΔH = +90 kJ/mol + +193 kJ/mol + +419 kJ/mol + (-325 kJ/mol) + (-691 kJ/mol)
ΔH = -314 kJ/mol
Therefore, the estimated δh⁰f for potassium bromide is -314 kJ/mol.
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determine the [f-] of the control sample (experimental step 5) by using the emeasured of the controlsample and the calibration curve (a plot of emeasured vs. log[f-] constructed by using standardsolutions) obtained from experimental step 4 (i.e., using the calibration curve). compare [f-]obtained from this method to the [f-] obtained with standard addition (experimental step 5). arethey similar? did you expect them to be similar or different? why?
The value of the Kf when molar concentrations of the ions present in an equilibrium system is 277.
The most effective technique to describe a solute concentration in a solution is by molar concentration. M = mol/L is defined as the total number of moles of solute dissolved in one litre of solution. All mole measurements are used to calculate the molar concentration, which is the volume of moles in the solution.
First part : Calibration curve is correct
slope of calibration curve is molar absorptivity = 5674 M⁻¹.cm⁻¹
Now to calculate Kf
Lets say we take,
Test Tube 1,
[FeSCN]₂⁺ eq = abs/molar absorptivity = 0.299/5674 = 5.3 x 10⁻⁵ M
Fe3⁺ + SCN⁻ <====> FeSCN2+
initial 0.002M x 3ml/10ml = 6 x 10⁻⁴ M 0.002M x 2ml/10ml = 4 x 10⁻⁴ M -
change -5.3 x 10⁻⁵ M -5.3 x 10⁻⁵ M +5.3 x 10⁻⁵ M
final 5.47 x 10⁻⁴ M 3.5 x 10⁻⁴ M 5.3 x 10⁻⁵ M
3. Kf = (5.3 x 10⁻⁵)/[(5.47 x 10⁻⁴)(3.5 x 10⁻⁴)] = 277
Similarly, you may do the calculation with other test tube solutions.
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what are the main sources of human-generated aerosols? choose all that apply. black carbon, which is generated by combustion processes and fires methane, a by-product of farming smoke sulfur dioxide emitted during the combustion of fossil fuels and as a consequence of burning vegetation to clear agricultural land chlorofluorocarbons emitted by industrial processes
The main sources of human-generated aerosols is sulfur dioxide emitted during the combustion of fossil fuels and as a consequence of burning vegetation to clear agricultural land, option C.
An aerosol is a suspension of minute liquid or solid particles in air or another gas. Aerosols can be produced intentionally or organically. Natural aerosols include fog or mist, dust, forest exudates, and geyser steam, to name a few.
Particulate air pollution, mist from hydroelectric dam discharge, irrigation mist, perfume from atomizers, smoke, dust, steam from a kettle, sprayed insecticides, and medications for respiratory disorders are a few examples of anthropogenic aerosols. An anthropogenic aerosol is inhaled when someone uses an electronic cigarette or vape pen.
A suspension is a combination of bigger particles with a substantial rate of settling; nevertheless, the difference between a suspension and an aerosol is not always obvious. The liquid or solid particles in an aerosol generally have diameters smaller than 1 m. Aerosol is a term that is frequently used in everyday speech to describe a system that dispenses consumer goods from cans.
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Write a balanced net ionic equation to explain the observed pH for each of the solutions tested.
a) Ammonium Chloride NH4Cl (4.4 - 4.8 pH).
b) Boric acid H3BO3 (4.4-4.8).
c) Borax Na2B4O7 (9-10).
d) Citric acid C6H8O7 (1.8-2.8).
e) Hydrochloric Acid HCl (1.8-2.8).
f) Sodium carbonate Na2CO3 (9-10).
a) Ammonium Chloride NH4Cl: NH4+ + H2O ↔ H3O+ + NH3
b) Boric acid H3BO3: H3BO3 + H2O ↔ H3O+ + B(OH)4-
c) Borax Na2B4O7: Na2B4O7 + 7H2O ↔ 2Na+ + 4B(OH)4- + 2OH-
d) Citric acid C6H8O7: H3C6H5O7 + 3H2O ↔ H3O+ + C6H5O73-
e) Hydrochloric Acid HCl: HCl + H2O ↔ H3O+ + Cl-
f) Sodium carbonate Na2CO3: Na2CO3 + H2O ↔ 2Na+ + HCO3- + OH-
These are the balanced net ionic equations that explain the observed pH for each of the solutions tested. The pH of a solution is determined by the concentration of hydrogen ions (H+) in the solution. In the above equations, the forward reaction represents the formation of hydrogen ions (acidic) and the reverse reaction represents the consumption of hydrogen ions (basic). The pH of a solution will be lower if the concentration of H+ is higher and higher if the concentration of H+ is lower. Based on the balanced net ionic equations above, solutions containing ammonium chloride, citric acid, and hydrochloric acid will have a lower pH (more acidic), while solutions containing borax and sodium carbonate will have a higher pH (more basic). Solutions containing boric acid will be slightly acidic due to the formation of H3O+ ions, but the pH will be close to neutral due to the equilibrium between the formation and consumption of H3O+ ions.
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if you have one molecule of tio2, how many molecules of o2 does it contain?
A single molecule of TiO2 (titanium dioxide) contains one titanium (Ti) atom and two oxygen (O2) atoms. However, it does not contain any O2 molecules, as O2 molecules consist of two oxygen atoms bonded together. In TiO2, the oxygen atoms are bonded to the titanium atom instead.
Titanium dioxide (TiO2) is a compound consisting of one titanium atom (Ti) and two oxygen atoms (O). Therefore, if you have one molecule of TiO2, it contains two molecules of O2.In TiO2, the titanium atom is bonded to two oxygen atoms through covalent bonds. Each oxygen atom contributes two electrons to form the covalent bonds with the titanium atom. This results in a stable structure with two oxygen atoms for each molecule of TiO2.
To break down the molecular composition further, the two oxygen atoms in TiO2 are not free O2 molecules. Instead, they are part of the chemical structure of TiO2 and are bonded to the titanium atom. The representation "O2" refers to two oxygen atoms bonded together, such as in the case of molecular oxygen (O2) gas.
In summary, one molecule of TiO2 contains two oxygen atoms. However, it's important to note that these oxygen atoms are not present as separate O2 molecules but are chemically bonded within the TiO2 compound.
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calculate the molarity of a solution containing 84 g of sodium fluoride dissolved in 0.5 l of water solution.
The molarity of the solution is 23 M or 23 mol/L.
To calculate the molarity of a solution, you need to know the number of moles of solute and the volume of the solution. The molarity is defined as the number of moles of solute per liter of solution, and it is typically expressed in mol/L or M.
In this case, we know that the solution contains 84 g of NaF (sodium fluoride) and that it is 0.5 L in volume. We also know that 1 mole of NaF contains 6.94 g of NaF.
To find the number of moles of NaF in the solution, we can use the molecular weight of NaF:
molar mass of NaF = 69.9 g/mol
number of moles of NaF = mass of NaF / molar mass of NaF
number of moles of NaF = 84 g / 69.9 g/mol
number of moles of NaF = 0.115 mol
To find the molarity of the solution, we can use the formula:
molarity = number of moles of solute / volume of solution
molarity = 0.115 mol / 0.5 L
molarity = 0.23 mol/L or 23 M
Therefore, the molarity of the solution is 23 M or 23 mol/L.
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The molar absorption coefficient of a solute at 540 nm is 386 dm3 mol−1 cm−1. When light of that wavelength passes through a 5.00 mm cell containing a solution of the solute, 38.5 per cent of the light was absorbed. What is the molar concentration of the solute?
The molar concentration of the solute is approximately 0.00110 mol/dm³.
The Beer-Lambert law states that:
A = εcl
where A is the absorbance, ε is the molar absorption coefficient, c is the concentration, and l is the path length.
In this problem, we are given the molar absorption coefficient (ε) at 540 nm, which is 386 dm3 mol−1 cm−1. We are also given the path length (l), which is 5.00 mm (or 0.5 cm). And we are given the absorbance (A), which is 38.5% of the incident light, or 0.385.
Using the Beer-Lambert law, we can solve for the concentration (c):
A = εcl
0.385 = 386 dm3 mol−1 cm−1 × c × 0.5 cm
Solving for c, we get:
c = 0.385 / (386 dm3 mol−1 cm−1 × 0.5 cm)
c = 0.0397 mol dm−3
Therefore, the molar concentration of the solute is 0.0397 mol dm−3.
In summary, we used the Beer-Lambert law to calculate the molar concentration of a solute in a solution based on the molar absorption coefficient, path length, and absorbance of the solution. The final answer is 0.0397 mol dm−3.
Using the given terms, the Beer-Lambert Law can be applied to calculate the molar concentration of the solute. The formula is:
A = ε × c × l
Where A is the absorbance, ε is the molar absorption coefficient (386 dm³ mol⁻¹ cm⁻¹), c is the molar concentration (mol/dm³), and l is the path length (5.00 mm or 0.5 cm).
First, find the absorbance (A) using the given percentage of absorbed light:
A = -log10(%Transmittance / 100)
A = -log10((100 - 38.5) / 100)
A = -log10(0.615)
A ≈ 0.212
Now, rearrange the formula to find the molar concentration (c):
c = A / (ε × l)
c = 0.212 / (386 × 0.5)
c ≈ 0.00110 mol/dm³
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Monomer liquid and polymer powder are each poured into a special holder called a(n): a. Injector b. Mold c. Resin d. Flask
Monomer liquid and polymer powder are each poured into a special holder called a(n) flask.
A flask is a special container used in dentistry to hold the liquid monomer and polymer powder during the process of making a dental prosthesis. This process is called denture fabrication or denture processing. The monomer liquid and polymer powder are mixed together in the flask, which is then placed in a pressure cooker called an autoclave. The heat and pressure from the autoclave cause the monomer and polymer to polymerize, or harden, into a solid form. Once the denture is processed, it can be removed from the flask and finished and polished to a high shine.
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