Answer: three primary types of bonding: ionic, covalent, and metallic. Definition: An ionic bond is formed when valence electrons are transferred from one atom to the other to complete the outer electron shell.
Explanation:
The nitrogen in a 30.0 L container at 740 torr and 55°C and the hydrogen in a 20.0 L container at 650 torr and 15°C are pumped into a 25.0 L container at 32°C. What is the final pressure?
Thus the final pressures of N₂ and H₂ are 825.7317torr and 550.6944torr respectively.
It is given that the Volume(V₁) of nitrogen is 30L and Pressure(P₁) of Nitrogen is 740torr and the temperature(T₁) is 55°C.
Similarly, for hydrogen, the volume(V₁) is 20L and Pressure(P₁) is 650torr and temperature(T₁) is 15⁰C.
These two are pumped into a container of Volume(V₂) of 25L and temperature (T₂) 32⁰C
To find the Final pressure of N₂, the following formula is to be used
P₁V₁/T₁ = P₂V₂/T₂
On substituting the values of P₁,V₁,T₁,V₂,T₂ we get P₂ of N₂ as,
(740x30)/328 = 25xP₂/305K
22200/328 = 25xP₂/305K
67.6829x305 = 25P₂
20643.2926/25 = P₂
825.7317torr = P₂
P₂= 825.7317torr
Therefore, the final pressure of N₂ is 825.7317torr
Similarly to find the final pressure of H₂ by applying the same formula we get,
P₁V₁/T₁ = P₂V₂/T₂
On substituting the values of P₁,V₁,T₁,V₂,T₂ we get,
(650x20)/288 = (P₂x25)/305
13000/288 = (P₂x25)/305
45.1388x305 = 25P₂
1376.3611/25 = P₂
550.6944 = P₂
P₂ = 550.6944torr
Therefore, the final pressure of H₂ is 550.6944torr.
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A compound has the composition 50.7% C, 9.9% H, and 39.4% N. What is the empirical formula?
Step 1
Empirical formula definition:
In chemistry, the empirical formula of a chemical compound is the simplest whole-number ratio of atoms present in a compound.
-----------------
Step 2
Information provided:
Composition,
50.7 % C
9.9 % H
39.4 % N
-----------------
Step 3
Assuming a 100 grams sample:
50.7 % C => 50.7 g C
9.9 % H => 9.9 g H
39.4 % N => 39.4 g N
-----------------
Step 4
The number of moles of each element is calculated as:
(Please, use your periodic table)
50.7 g C x (1 mole C/12.01 g C) = 4.22 moles C
9.9 g H x (1 mole H/1.008 g H) = 9.82 moles H
39.4 N x (1 mole N/14.00 g N) = 2.81 moles N
-----------------
Step 5
Each number in step 4 will be divided by the smallest one of the 3. It is also needed integer numbers.
4.22 moles C/2.81 moles N = 1.5
9.82 moles H/2.81 moles N = 3.5
2.81 moles N/2.81 moles N = 1
As we need integer numbers, we will multiply all these numbers by 2 as it follows:
C => 1.5 x 2 = 3
H => 3.5 x 2 = 7
N => 1 x 2 = 2
Therefore, the empirical formula will be:
Answer:
[tex]C_3H_7N_2[/tex]How many atoms are in 8.37 mol of Lithium?
ANSWER
he number of atoms of lithium is 5.039 x 10^24 atoms
EXPLANATION
Given that;
The number of moles of lithium is 8.37 mol
Follow the steps below to find the number of atoms of lithium
[tex]\text{ mole = }\frac{\text{ number of atoms}}{\text{ Avogadro's number}}[/tex]Recall, that the Avogadro's number is 6.02 x 10^23
[tex]\begin{gathered} \text{ mole = }\frac{\text{ Number of atoms}}{\text{ Avogadro's number}} \\ \\ \text{ 8.37 = }\frac{\text{ number of atoms}}{\text{ 6.02 }\times\text{ 10}^{23}} \\ \text{ cross multiply} \\ \text{ Number of atoms = 8.37 }\times\text{ 6.02 }\times\text{ 10}^{23} \\ \text{ Number of atoms= 50.39 }\times\text{ 10}^{23} \\ \text{ Number of atoms = 5.039 }\times\text{ 10}^{24}\text{ atoms} \end{gathered}[/tex]Therefore, the number of atoms of lithium is 5.039 x 10^24 atoms
What is the ph of a buffer that was prepared by adding 3. 96 g of sodium benzoate, nac7h5o2, to 1. 00 l of 0. 0100 m benzoic acid, hc7h5o2? assume that there is no change in volume. The ka for benzoic acid is 6. 3 × 10–5.
The pH of a buffer that was prepared by adding 3. 96 g of sodium benzoate, NaC₇H₅O₂, to 1.00 L of 0.0100 M benzoic acid, HC₇H₅O₂ is 4.63.
Given that :
Ka = 6.3 × 10⁻⁵
The equation :
HA + H₂O ----> H₃O⁺ + A⁻
A⁻ = C₇H₅O₂⁻
The formula is given as :
pH = pKa + log [A⁻] / [HA⁻]
pKa = - log Ka = - log ( 6.3 × 10⁻⁵ ) = 4.20
[A⁻ ] = [C₇H₅O₂⁻] = NaC₇H₅O₂
= 3.96 g / 144.10 g
= 0.0274 / 1 L = 0.027 mol / L
[HA] = 0.0100 moll / L
substituting the value in the formula:
pH = pKa + log [A⁻] / [HA⁻]
pH = 4.20 + log ( 0.0274 / 0.0100 )
= 4.20 + 0.439
= 4.63
pH = 4.63
Thus, The pH of a buffer that was prepared by adding 3. 96 g of sodium benzoate, NaC₇H₅O₂, to 1.00 L of 0.0100 M benzoic acid, HC₇H₅O₂ is 4.63.
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9) Boron (B) + Nitrogen (N)
Answer:
if u combined them itd would be BN
Determine the Energy of light whose frequency is 5.678 x 105 Hz. What type of radiation is it?
Answer:
Energy = 3.77 × 10⁻²⁸ J; radio wave.
Explanation:
In order to calculate the energy of an electromagnetic wave given its frequency, we have to use the following formula:
[tex]\boxed{E = hf}[/tex],
where:
• E = energy of wave
• h = Planck's constant (6.63 × 10⁻³⁴ m² kg / s)
• f = frequency of wave (5.68 × 10⁵ Hz)
Using the formula and information above, we can calculate the energy of the wave:
E = 6.63 × 10⁻³⁴ × 5.68 × 10⁵
= 3.77 × 10⁻²⁸ J
Therefore, the energy of the wave is 3.77 × 10⁻²⁸ J, and it is a radio wave, as radio waves have frequencies of magnitude 10⁴ to 10⁵ Hz.
Hello i need help please Questions 1 and 2 (lipids)
The question requires us to complete the sentences regarding characteristics and properties of lipids.
First, we need to keep in mind what are lipids: these essential molecules to cell's membranes are typically made of a glycerol backbone, fatty acid "tails" (the hydrofobic part) and and a phosphate group (a hydrophilic part). The term "lipids" is commonly used as a synonym for "fats", which it isn't completely wrong as they share many properties (for example, lipids don't mix with water).
As they are organic molecules, all lipids have carbon, oxygen and hydrogen in their structure, while some of them can contain other elements (such as phosphorus for the phospate group and nitrogen).
Considering the information above, we can complete the sentences as:
1. "Lipids is a general term describing organic molecules that are insoluble in water".
2. "All lipids are made of carbon, hydrogen and oxygen, while some lipids contain other elements..."
Question 5
What's the problem with non-renewable resources?
Question 5 options:
A. They are used at a rate much slower than they are formed.
B. Given enough time, we run out of them.
C. They are easily recycled.
The problem with non-renewable resources is given enough time, we run out of them
Non renewable resources means the energy resources include coal, natural gas, oil and also nuclear energy and once this resources are used up then they cannot be replaced again which is the major problem fir humanity and if we run out of non renewable resources then the global economy will be constrained to a semi local condition as there will be no more fuel to move product around so this is also the problem with non renewable resources
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Which best explains why h2o has a much higher melting and boiling point than co2?.
Because water is a polar molecule and carbon dioxide is a nonpolar molecule, water has a greater boiling point than carbon dioxide. Since polar molecules have greater intermolecular interactions than nonpolar ones, polar molecules like water require more energy or heat to disintegrate.
Why is the boiling point of water higher?It is highly challenging to break the bonds that make up the massive water molecule due to its substantial hydrogen bonding.
The boiling point tells you what?The temperature at which a chemical's vapor pressure equals atmospheric pressure is known as the boiling point.
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what do the coefficients in a balanced equation tell us? mark all that apply. group of answer choices the relative volume of each substance involved in a reaction. the number of molecules of reactants and products involved in a chemical reaction. the relative number of moles of each substance involved in a chemical reaction. the relationships between the masses of the reactants and/or products in a reaction.
The coefficient in an equation for a chemical reaction that is balanced reveals some details about the chemical process.
What is balanced chemical reaction?An equation for a chemical reaction is considered to be balanced if both the reactants and the products have the same number of atoms and total charge. In other words, the mass and charge balances on both sides of the reaction are equal.
The coefficient in a balanced chemical reaction equation provides us with the following details about the reaction:
Coefficient tells us, the relative number of moles of each substance involved in a chemical reaction.
For example,
2H₂ + O₂----> 2 H₂O
That's mean, 1 moles of oxygen gives 2 moles of H₂O on reacting with 2 mol of Hydrogen.
The coefficient in a chemical equation tells us also, the number of molecules of reactants and
products involved in a chemical reaction. For example,
N₂ + 3 H₂. -----> 2 NH₃.
Their are, 1 molecule of Nitrogen and 3 molecules of Hydrogen gives 2 molecules of NH₃. therefore
coefficient tells us this information also.
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Which of the following would be evidence of a
chemical change? Boiling or Burning
Evidence of a chemical change will be Burning.
Changes are either classified as physical or chemical changes. Chemists learn a lot about the nature of matter by studying the changes that matter can undergo.
A change can be physical if no ties are made or broken. They entail rearranging molecules but do not alter them.
A few examples of physical changes are:. shifts in state (changes from a solid to a liquid or a gas and vice versa).
When bonds between molecules or atoms are created, disrupted, or both, chemical changes result. This implies that a substance with a particular set of properties—such as melting point, color, flavor, etc.—becomes a substance with a different set of characteristics.
The burning of paper and cloth involves both a physical and a chemical change, which can be reversed more easily than the boiling or heating of water. If water is boiled for more time it changes from a chemical state to a vapor state, which is a physical change.
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A diatomic molecule has 16 valence electrons. Using mo theory, what can you conclude about this molecule? select all of the correct answers.
For stability of any molecule or element , molecule has to follow octet rule. There are so many exceptions to this rule. the correct option is option D
What is octet rule?According to octet rule an element or molecule is stable only if it contains 8 electron in its valence shell
According to our question there all valence electron total of 16 electron. This electron is counted by adding bonding and nonbonding electron. If there will be total valence electron of 16 or more than this then there must be expanded octet which leads to instability. For this reason there must be valence electron less than 16
Therefore No, the octet rule means there are 8 valence electrons around each atom, but bonding electrons get counted for the atoms on both sides of the bond, so there are normally fewer than 16 valence electrons unless there is an expanded octet. The correct option is option D
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Your question is incomplete, but most probably your full question was,
Does the octet rule mean that a diatomic molecule has 16 valence electrons? Select from the following:
A. Yes, each atom has 8 valence electrons. Two atoms, with 8 electrons each, is 16 valence electrons.
B. No, the octet rule means there are always 8 valence electrons and only 8 valence electrons.
C. Most of the time there are 16 valence electrons, but there are exceptions to the octet rule (odd-electron species, expanded octets, etc.) that could make it more or less than 16.
D. No, the octet rule means there are 8 valence electrons around each atom, but bonding electrons get counted for the atoms on both sides of the bond, so there are normally fewer than 16 valence electrons unless there is an expanded octet.
What is a water molecule composed of?
Answer:
c Two hydrogen one oxygen
Explanation:
H2O
An unknown metal has a mass of 51.842 grams. When placed in a graduated cylinder, the volume of water rose from 17.1 mL to 19.8 mL. What is the identity of the metal?
Copper: density = 8.96 g/mL
Brass: density = 8.73 g/mL
Gold: density = 19.2 g/mL
Strontium: density = 2.54 g/mL
The identity of the unknown metal that has a mass of 51.842 grams when placed in a graduated cylinder is gold with 19.2g/mL.
How to calculate density?Density of a substance is a measure of the mass of matter contained by a unit volume. The density of a substance can be calculated by dividing the mass of the substance by its volume as follows:
Density = mass ÷ volume
According to this question, an unknown metal has a mass of 51.842 grams. When placed in a graduated cylinder, the volume of water rose from 17.1 mL to 19.8 mL.
Volume of the metal = 19.8mL - 17.1mL = 2.7mL
Density = 51.842g ÷ 2.7mL
Density = 19.2g/mL
Gold has a density of 19.2g/mL, hence, confirms the identity of the metal.
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describe the property of the substances in the water that is used to remove each substance from the water.
Answer:
Explanation:
Think about the example of a mixture of salt water. The salt is a non-volatile ionic compound - this means it is very difficult to turn salt into a gas. It takes very high temps just to melt the salt.
The water is a volatile molecular compound which can be heated to the boiling point fairly easily. This leads to vaporization which turns the liquid water into steam.
So heating a solution of salt water allows you to separate the water from the salt.
Where are the products in a chemical equation located?
O A. Between the reactants of the chemical equation
OB. On the left side of the arrow in the equation
O C. At the beginning of the chemical equation
D. On the right side of the arrow in the equation
for a particular isomer of c8h18, the combustion reaction produces 5108.7 kj of heat per mole of c8h18(g) consumed, under standard conditions. c8h18(g) 252o2(g)⟶8co2(g) 9h2o(g)δH∘rxn
The enthalpy of formation of the compound is -230.3 kJ/mol.
What is the heat of formation?We know that the heat of formation of a substance can be obtained from the equation; [tex]C_{8} H_{18} (g)+\frac{25}{2} O_{2} (g)-------- > 8CO_{2}(g)+9 H_{2}O[/tex](g)ΔH∘rxn=−5093.7 kJ/mol by the use of the Hess law.
Let us now obtain the heats of formation of each of the species in the reaction as we can see them from the species in the reaction equation;
[tex]CO_{2}[/tex](g) = -393.5 kJ/mol
[tex]H_{2} O[/tex](g) = -241.82 kJ/mol
[tex]O_{2}[/tex](g) = 0 kJ/mol
The enthalpy of formation of the compound is now;
8(-393.5) + 9( -241.82) + 5093.7
= -3148 -2176 + 5093.7
= -230.3 kJ/mol
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How did the improvement of the telescope contribute to the modern model of the solar system? (1 point) the improve telescope showed scientists that the solar system contained planets. the improve telescope showed scientists that the solar system contained stars. the improve telescope showed scientists that the solar system contained moons. the improve telescope showed scientists that the solar system contained comets.
The improved telescope showed scientists that the solar system contained comets.
What is the solar system?The solar system has to do with the arrangement of the sun and the planets. The sun lies at the center of the solar system and then the sun is surrounded by the planets that move all around the sun in concentric circles.
Now we know that the telescope is the kind of object that could be used in the study of the outer space. We could use it to study the stars as well as other celestial bodies in the study of astronomy.
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hypothesis: is the Oobleck going to turn into a solid or liquid?
The Oobleck mixture is neither a liquid nor a solid. The cornstarch-and-water solution produces a fluid that behaves more like quicksand than water applying force causes it to thicken.
What is mixture?A mixture is a substance made up of two or more chemical components that do not combine chemically.
A compound produced by combining two or more different ingredients without triggering a chemical reaction is another way to describe it.
There are two types of mixture.
Homogenous mixture -The most common example of a homogeneous mixture is sugar and water. Homogeneous mixtures are those that have the same properties and combinations throughout their mass.Heterogeneous mixture - A heterogeneous mixture is one that contains both sand and salt. Heterogeneous mixtures indicate that the qualities are not consistent throughout the entire combination by having varied properties and compositions in different portions of the mixture.Thus, the Oobleck mixture is neither a liquid nor a solid. The cornstarch-and-water solution produces a fluid that behaves more like quicksand than water applying force causes it to thicken.
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What idea does the Law of Definite Proportions support?(1 point) Responses the existence of mass the existence of mass the continuous theory of matter the continuous theory of matter the existence of elements the existence of elements the particulate theory of matter
Answer:
A.the particulate theory of matter
Explanation:
Law of Definite proportions support the particulate theory of matter.
The law of definite proportions states that a given chemical compound always contains the same elements in the exact same proportions by mass.
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This pizza is placed in this oven in order to bake. What type of energy is used to bake the pizza?
A Radiant
B Thermal
C Mechanical
D Electrical
Thank you for your help
Answer:
A
Explanation:
Radiant energy.......
what property of dishwashing liquid (detergent) makes it useful to wash grease from pans?
Dishwashing liquid (detergent) is useful for removing grease from pans due to its amphipathic character.
Grease is a type of liquid lubricant that has thickening agents dispersed throughout it. It can also be solid or semisolid. A soap is typically emulsified with mineral or vegetable oil to form grease.
One typical characteristic of greases is that they have a high initial viscosity, which, when sheared, decreases to create the impression of an oil-lubricated bearing with a viscosity that is roughly equal to the base oil used in the grease. Shear thinning refers to this change in viscosity. Sometimes the term "grease" is used to refer to lubricating substances that are merely soft solids or highly viscous liquids; however, these substances lack the shear-thinning characteristics of traditional grease. For instance, petroleum jellies like Vaseline aren't typically categorized as greases.
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What are some positive and negative economic, social, political and environmental impacts related to the mining, use or disposal of copper?
Suppose that some hydrochloric acid is placed in a beaker and a pH meter is set into the solution. It reads pH 1.5.
(a) Describe how the pH will change when a small amount of NaOH solution is added drop by drop to the acid. t
(b) Explain why the pH will change.
Answer:
A) The pH will increase.
B)The pH will change because the solution is being neutralized via a basic solution being added to an acid.
what is the difference between the volume of edta used to titrate the sample and the volume of edta that reacted with the blank? quilzet
The most prevalent indicators used in complexometric titrations are organic dyes, which work by generating a clouded complex with the metal ion under test.
The indicator is replaced by EDTA during the reaction to create a more stable complex with the metal, and after the reaction is finished, the colour is changed.
The acronym EDTA stands for ethylenediaminetetraacetic acid. For the titration, an excessive amount of EDTA is used to react with the sample solution's calcium and magnesium ion titrations. When the indicator is applied, it stays blue because the EDTA has complexed with all of the Ca2+ and Mg2+ ions present for titrations.
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The concentration f the sugar glucose (c6h12o6) in human blood ranges from 80 mg/dl before meals up to 120 mg/dl after eating. find the molarity of glucose in blood before eating. remember 1 dl = 0.1l
The molarity of glucose in blood before eating is 0.00666 M
Molar concentration is the degree of the concentration of a chemical species, especially of a solute in a solution, in phrases of quantity of a substance per unit quantity of answer. In chemistry, the most usually used unit for molarity is the variety of moles in line with liter.
We are given the human blood ranges from about 80 mg/dL before meals to 120 mg/dL after eating.
1 dL = 0.1 L
Mass of glucose before meal = 80 mg = 0.080 g
Mass of glucose after eating = 120 mg = 0.120 g
So, moles of glucose = 0.080 g / 180.16 g/ mol
= 0.000444 moles
Moles of glucose = 0.120 g / 180.16 g/mol
= 0.000666 moles
So, molarity of glucose in blood before eating = 0.000444 moles / 0.1 L
= 0.00444 M
molarity of glucose in blood after eating = 0.000666 moles / 0.1 L
= 0.00666 M
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The 5 human impacts on erosion are
a. Construction, deforestation, agriculture, overgrazing
b. Construction, planting, agriculture, overgrazing, urbanization c Urbanization, buildings, deforestation, agriculture, overgrazing
d. Construction, deforestation, agriculture, overgrazing, urbanization
d. Construction, deforestation, agriculture, overgrazing, urbanization
The process of removing soil, rock, or dissolved material from one area on the Earth's crust and moving it to another, where it is deposited, is known as erosion. Erosion differs from weathering, which is a static process.
Earthen materials are worn away during erosion, a geological process in which they are moved by wind or water. Weathering, a related process that does not involve movement, dissolves or breaks down rock.
The movement of loose rock, soil, and sand fragments from one place to another is called erosion. All landforms on the earth's surface, including mountains, deserts, and coastlines, are impacted by erosion. One of the main reasons for erosion is water.
the effects of erosion
decreased capacity of the soil to store nutrients and water.subsoil exposure, which frequently has undesirable physical and chemical characteristics.greater runoff rates, wasting water and nutrients that would have been used to cultivate crops.crop loss in newly planted fields.Silt accumulations in low-lying places.To know more about erosion, click on the link below:
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How does the Sun's gravity compare to the Earth's gravity? a a. The Sun's gravity is stronger b b. The Earth's gravity is stronger c. Their gravitational pull is the same d. Scientists aren't able to measure the Sun's gravity
Answer: A. The sun's gravity is stronger.
Explanation: Gravity has to do with 2 factors, the mass of the object and the distance between the 2 objects.
The Sun's mass is immensely larger than the Earth's mass, so the sun's gravity would be stronger.
the reaction described in part a required 3.92 l of magnesium chloride. what is the concentration of this magnesium chloride solution?
A)compute the mole of AgNO3 first.
volume, when V=1.92 L
use:
amount of mole,
n = Volume * Molarity
= 0.18*1.92
= 0.3456 mole
In light of the balanced equation
AgNO3 = (2/2)*moles of AgCl produced
= (2/2)*0.3456
= 0.3456 mole
This is the quantity of AgCl moles.
AgCl molar mass,
MM equals 1*MM(Ag) + 1*MM (Cl)
= 1*107.9 + 1*35.45
= 143.35 g/mole
use: volume of AgCl,
M = Molar Mass * Molar Number
= 1.434*102 mole/mole x 0.3456 mole
= 49.54 g
Response: 49.5 g
B)Here: AgNO3 = M=0.18 M
V(AgNO3)=1.92 liters
V (MgCl2) = 3.83 L
A balanced response states:
1 mole of AgNO3 = 2 mole of MgCl2, and vice versa.
2*M(MgCl2)*V = 1*M(AgNO3)*V(AgNO3) (MgCl2)
1*0.18*1.92 = 2*M(MgCl2)*3.83
0.0451 M (MgCl2)
Response: 0.0451 M
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Which of the following statements correctly describe CH3COOH (acetic acid)?
a. There are 2 atoms of carbon in one molecule of acetic acid
b. The molar mass of acetic acid is 29.02 g/mol.
c. There are 16.00 amu of oxygen per molecule of acetic acid.
d. There are 4 moles of hydrogen atoms per mol of acetic acid.
The following statements from the given questions are correct.
There are 2 atoms of carbon in one molecule of acetic acid.
There are 4 moles of hydrogen atoms per mol of acetic acid.
If we look at the chemical formula of the acetic acid (CH3COOH) There are two carbon atoms.
The number of moles of Hydrogen is four because there are 4 hydrogen atoms present in acetic acid.
The remaining options are incorrect because the molar mass of acetic acid is 60.05 g/mol and there are 32.00 amu of oxygen per molecule of acetic acid.
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