When two compounds are combined and change into a third substance, this is referred to as a biochemical reaction (or chemical reaction). When two substances are combined, not all of them react chemically.
How does chemical change?When one chemical material changes into one or more others, as when iron rusts, this is referred to as a chemical transformation. Chemical reactions produce changes in the way that molecules and atoms are ordered, which leads to the formation of new substances with new properties.
Describe a chemical example:Examples for chemicals include the basic building blocks, such as zinc, nitrogen, and oxygen; combinations created from these building blocks, such as water, dioxide, or salt; and more complicated substances, such as the air you breathe, rainfall, a chicken, a car, etc.
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I need this answer somebody Please help me
The correct responses that describe the various rules in the filling of orbitals are;
1) Aufbau principle
2) Pauli exclusion principle
3) Hund's rule.
What is the orbital?The orbital has to do with the region in space where there is a high probability of finding the electron. We have to know that that looking at the orbitals, we can know how electrons are arranged in the atoms in order of increasing energy.
The Aufbau principle shows us that when we try to fill the electrons into orbitals, we must start from the orbital that has the lowest energy. The Pauli exclusion principle states that no two electrons in an atom can have the same value for all the four quantum numbers. In other words, electrons in the same orbital must have anti parallel spins.
Also, when we are filling electrons into orbitals that have the same energy, we fill them in singly first. This is the statement of the Hund's rule.
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given the electronegativity values of c (2.5), n (3.0), o (3.5), and s (2.5), which of the following molecules have polar bonds? question 34 options: a) smog, no2 b) carbon dioxide, co2 c) sulfur dioxide, so2 d) all of the above e) none of the above
Given the electronegativity values of c (2.5), n (3.0), o (3.5), and s (2.5), The following molecules have polar bonds answer is all of the above.
There is bond between carbon and oxygen. So , bund is polar . since they have different electro negativities
The electronegativityes O' and s'are different. so, bond is polar and There is difference is electronegativityes between N and O, Sois polar bond.
When an atom of a certain chemical element forms a chemical bond, it has a propensity to draw shared electrons, which is denoted by the symbol, which stands for electronegativity. The atomic number of an atom and the separation of its valence electrons from the charged nucleus both have an impact on how electronegtive that atom is. The atom is more in need of an electron when the electronegativity is higher. o Electronegativity grows across a period from left to right. o The attraction of an atom on the electrons in a bonding pair is strongest when the valence shell is nearly full.
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Put the following elements in order from smallest to largest atomic radius: Carbon, Oxygen, Tin, Strontium
The order of the elements from smallest to largest atomic radius are O<C<Sn<Sr.
What is the definition of an atom's atomic radius?Atomic radius is the separation between an atom's outer electron shell and nucleus. 1/2 the distance between identical atoms that are bound together by their nuclei. Positively charged ions known as cations are smaller than their neutral atom.
Therefore, The distance between the center of the nucleus and the biggest shell inhabited by the valence electron of a neutral element is known as the atomic radius, which is an attribute of atoms. This would rely on the atom's atomic number and the quantity of electrons it contains.
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The distance of a doorknob from the floor is about 1
The ideal distance between a doorknob and the the ground floor is 34 inches.
How far should a doorknob and floor?In a lay man language, a doorknob simply refers to the handle which is usually used to hold doors in order to open or close the door. Every door of a building regardless of its size or location in the building must have a knob to always hold it with .
However, from the task given above, a doorknob should be at least 34 inches from the floor under normal circumstances.
In conclusion, it can be deduced from the simple explanation above that a doorknob should be ideally 34 inches from the floor of the house or building.
Complete question:
What should be the ideal distance between the doorknob from the floor?
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three naturally occurring isotopes of an element are shown in the models below. what do the isotopes have in common?
same number of protons but different numbers of neutrons.
Isotopes are members of a family of an element that all have the same number of protons but different numbers of neutrons.
Isotopes are atoms of the same element that have different numbers of neutrons but the same number of protons and electrons. The difference in the number of neutrons between the various isotopes of an element means that the various isotopes have different masses.
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a chemical equation that shows all reactants and products as intact, undissociated compounds is called a(n)
Answer: molecular equation
Explanation:
given 5.86 moles of NaN3, how many moles of Na are produced?
When 5.86 moles of NaN3(Sodium Azide) is given then no. of moles of Na produced is 5.86 mol.
What is NaN3 (Sodium Azide)?The inorganic substance with the formula NaN3 is sodium azide. The gas-forming element in older automotive airbag systems is this colourless salt. It is utilised to make additional azide chemicals. It is an ionic chemical that is exceedingly water soluble and extremely dangerous.
What Na Describes?Na is the chemical formula used for the element having atomic number 11 and called as Sodium
Acc. to the given data following is the reaction occurring
2NaN3→2Na+3N2
Now to calculate the no. of moles of Na
Multiply the given moles of sodium azide(NaN3) by the mole ratio between NaN3 and N2 from the balanced equation, with Na in the numerator. 2 mol Na:3 mol N2
5.86 molNaN3×2mol Na/2mol NaN3=5.86 mol Na
Hence, when 5.86 moles of NaN3(Sodium Azide) is given then no. of moles of Na produced is 5.86 mol.
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sodium hydroxide (naoh) is a notably common strong base. it is used in household cleaning, drain clearing, tissue digestion, chemical pulping, and german pretzel production (which thankfully uses food grade sodium hydroxide, which is rare.) a. to prepare a solution for an important reaction, a scientist places 40 g of naoh in 2 l of water. what is the poh of this solution? what is the ph of this solution?
The pOH of this solution is 0.3 and the pH of the solution is 13.3 .
What is pH ?
The pH of a food is a direct function of the free hydrogen ions present in that food. Acids in food release free hydrogen ions. Hydrogen ions give acidic foods their characteristic sour taste. Therefore, pH can be defined as a measure of free acid. More specifically, pH is defined as the negative logarithm of hydrogen ion concentration. The pH range is 0 to 14. The pH of pure water is exactly 7, so pH 7 is neutral. Values less than 7 are acidic. Values above 7 are basic or basic.
Foods are generally classified as “acidic foods” (low pH, pH 4.6 or less) or “weakly acidic foods” (high pH, pH 4.6 or higher). Safe food storage is determined by the pH of the food. Acidic foods such as fruit and pickles can be safely canned in a tin can with a hot water bath. A combination of acid and hot water (212°F) destroys perishable organisms such as mold and yeast. Proper cooking water canning processes are important to prevent the growth of acid-tolerant molds and yeasts that can lead to elevated pH levels. The pH of borderline foods such as figs and tomatoes can easily exceed 4.6, so lemon juice or citric acid should be added before canning with boiling water. Low-acid foods such as vegetables and meat should be processed in a pressure preserver for safety.
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Which structure is the arrow pointing to?
What is the function of this organelle?
The structure the arrow is pointing to is the nucleus and it helps store genetic material (DNA) in living cells.
What is an organelle?Organelle is a specialized structure found inside cells that carries out a specific life process. examples are ribosomes, vacuoles, nucleus etc.
The nucleus is the large membrane-enclosed organelle found in eukaryotic cells which contains genetic material.
The nucleus is located at the center of living cells and it functions to store genetic material called DNA. The DNA is transferred to offsprings for inheritance of traits.
According to this question, a microscopic image of a cell is shown. The arrow pointed to the nucleus of the cell.
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the bromophenol blue endpoint is surpassed in the back titration of the excess hcl with the sodium hydroxide titrant. as a result of this technique error, will the reported amount of antacid in the sample be too high or too low? explain.
The reported amount of antacid in the sample will be too high.
What are antacids?
Antacids are simply assembled salts and salk like compound which help in neutralizing of acids.This Neutralization reaction by antacids leads to various products such as other salts, water and possibly carbondioxid which results in hydrolysis and insoluble compound precipitation. There is a noticeable decline in the neutralizing ability by antacids and neutralization rate of aluminum-containing antacids when they are neutralized ny antacids in the presence of organic acids, peptones, and polypeptides.
In above case, the reported amount of antacid will be high because it will report as more NaOH needed to neutralize a greater amount of HCl.
Hence, The reported amount of antacid will be too high.
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The sample's antacid content will be overstated in the reported amount.
What are antacids?
Simple salts and salk-like compounds that are assembled to form antacids aid in neutralising acids. Antacids' neutralisation reaction produces a number of byproducts, including other salts, water, and possibly carbon dioxide, which causes hydrolysis and the precipitation of insoluble compounds. When aluminum-containing antacids are neutralised by antacids inside the presence of organic acids, peptones, and polypeptides, there is a discernible decline in their ability to neutralise and rate of neutralisation.
In the aforementioned situation, the reported amount of antacid would be high because more NaOH will be required to neutralise a larger amount of HCl.
Hence, The reported amount of antacid will be too high.
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How many molecules are found in 25.00 moles of Sucrose Sugar, or C12H22O11?
Taking into account the definition of Avogadro's Number, 1.50575×10²⁵ molecules are found in 25.00 moles of Sucrose Sugar.
Avogadro's NumberAvogadro's number is currently defined as the number of atoms in 12 grams of carbon-12 and its known approximate value is 6.023×10²³.
In other words, Avogadro's Number is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance.
Amount of atoms in 25.00 moles of Sucrose Sugar
You can apply the following rule of three: if by definition of Avogadro's Number 1 mole of sucrose sugar contains 6.023×10²³ molecules, 25 moles of the compound contains how many molecules?
amount of molecules of sucrose sugar= (25 moles × 6.023×10²³ atoms)÷ 1 mole
amount of molecules of sucrose sugar= 1.50575×10²⁵
Finally, in 25.00 moles of Sucrose Sugar are present 1.50575×10²⁵ molecules.
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the compound ccl4 contains question 16 options: a) nonpolar covalent bonds. b) polar covalent bonds, with partial negative charges on the cl atoms. c) ionic bonds. d) polar covalent bonds, with partial negative charges on the c atoms.
The compound [tex]CCl_{4}[/tex] contains polar covalent bonds having partial negative charges on the Cl atoms.
So, the correct option is B.
The four polar covalent bonds between carbon and chlorine in carbon tetrachloride ( [tex]CCl_{4}[/tex]) give it its name as a covalent compound. Due to the variation in atoms' values of electronegativity, the bonds in this compound are polar. The molecule is asymmetrical, which means that the opposing opposite forces balance each other out, and as a result, the molecule is not polar.
The four bonds have symmetry and are spread out in four different directions. In each order, the dipole moments are thus canceled out. Tetrachlorocarbon is a non-polar molecule as a result. Although the electronegativities of C and Cl are different, the carbon tetrachloride molecule has no dipole moment.
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why is a double or triple bond needed? select all that apply. serves as a source of electron density serves as a nucleophile serves as an electrophile serves as a source of electron deficiency
The double or triple bond are needed because as they serves as a source of electron density and serves as a nucleophile.
The double bond or triple bond are electron rich entities capable of donating electrons thus act as nucleophile (species that donate electrons) and serve as electron dense region in molecules.
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suppose you need to prepare 100. ml of a solution with the 6.0 mg/l concentration of a dye and what you have is a 30. mg/l stock solution of the dye and pure water. what amounts of the liquids should be mixed?
To prepare 100ml of a solution with the 6.0mg/l concentration of a dye and you have a 30 mg/l stock solution of the dye and pure water, 20 ml of pure water should be mixed.
Solutions are made diluting more concentrated stock solutions.certain volume of the stock solution is transferred to a new container and is brought to a new volume.since, the total volume of solute is the same before and after dilution.
C0 V0 = CdVd
Where, C= concentration of stock solution
V= diluted volume of the stock solution
C= concentration of diluted solution
V= volume of the diluted solution
Here putting the values,
30 mg/l * vo = 6.0 mg/l * 100ml
VO = 20ml
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a 125 g sample of lead at 85.0 c and a 320 g sample of silver at 34.0 c are added to 0.500 kg of water at room temperature (22.0 c) in an insulated container. assuming the system is thermally insulated, what is the final equilibrium temperature?
The final equilibrium temperature of the mixture of lead, silver, and water is 24.65°C. The result is obtained by using the Black's Principle.
What is Black's Principle?The Black's Principle states that heat released by a higher-temperature object is equal to the heat absorbed by a lower-temperature object. It can be expressed as
Q release = Q absorbs
Where
Q release is the heat released by high-temperature objects.Q absorb is the heat absorbed by low-temperature objects.The mass of lead is 125 g at 85°C, the mass of silver is 320 g at 34°C, and the mass of water is 0.5 kg at 22°C. All of them are mixed, so that the temperature of the lead and silver will fall and otherwise the temperature of water will rise.
The equation of the heat energy with the temperature change is
Q = m × c × ΔT
Where
m = massc = specific heat capacityΔT = change in temperatureThe data shows that:
c lead = 128 J/kg °Cc silver = 234 J/kg °Cc water = 4,186 J/kg °CThe equilibrium temperature is
Q release = Q absorbs
(m × c × ΔT)lead + (m × c × ΔT)silver = (m × c × ΔT)water
(0.125 × 128 × (85-T)) + (0.320 × 234 × (34-T)) = (0.500 × 4,186 × (T-22))
(16 × (85-T)) + (74.88 × (34-T)) = (2,100 × (T-22))
1,360 - 16T + 2,545.92 - 74.88T = 46,200 - 2,100T
2,190.88T = 50,105.92
T = 24.65°C
Hence, the final equilibrium temperature of the mixture is 24.65°C.
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How is the bent geometry related to the trigonal planar geometry?
They are related through the trigonal planar being the electron geometry and bent is the molecular geometry for an element that has two bonds and one lone pair.
What is Geometry?This is referred to as the study of different types of shapes, figures and sizes and is used in various fields such as mathematics, chemistry etc.
In the field of chemistry, there are different types such as trigonal planar and the bent geometry which are related as a result of some shared characteristics which include the following in the subsequent paragraph.
They are related through the trigonal planar being the electron geometry and bent is the molecular geometry for an element that has two bonds and one lone pair and is therefore the correct choice in this scenario.
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which of the following pairs of compounds could be separated by chemically active extraction? what reagents would you use? a. ch3ch2co2h and clch2ch2co2h b. phenol and alcohol c. nh and o
Option-(b) Phenol and alcohol could be separated by chemically active extraction.
In the chemically active extraction ,the compounds are treated with an acid or a base to alter their chemical structure. There are 3 types of chemical extraction. liquid-liquid, liquid-solid and acid base extraction. Acid-base extraction is known as a chemically active extraction.
A phenol is a weak acid.it can lose hydrogen ion when dissolved in water. alcohol is both acid and a base.it reacts with a strong base. The Oxygen atom makes alcohol a base. phenol and alcohol treated with DNA in the process of active extraction.
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in the laboratory you dilute 4.90 ml of a concentrated 12.0 m hydrochloric acid solution to a total volume of 175 ml. what is the concentration of the dilute solution?
The diluted hydrochloric acid solution had a concentration of 0.3M
what is dilution?
Dilution is the application of a solvent that reduces the concentration of the solute with in solution. Concentration is the elimination of solvent, which raises the concentration of the solute in the solution.
The hydrochloric acid chemical formula is HCL,
if 1 liter of the HCL has 12mol, then 4.90ml or 0.0049 L of solution has 0.058 moles,
When the acid solution was diluted , we will get 175ml or 0.175 L
so as we dilute the solution we will have the change in the concentration and that is calculated
0.058/0.175=0.3314
=0.3M
So the concentration of the solution that is diluted was found to be 0.3M
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Which selection best describes what granger believes to be the major difference between man and the phoenix?.
The statement best describes what Granger believes to be the major difference between man and the phoenix: that the phoenix recognizes when they have made a mistake and eventually will learn not to repeat it. Meanwhile, although a man recognizes his fault, he will continue to repeat them.
What does Granger say about the men and phoenix comparison?
Phoenix is a mythological creature that would burn itself to death only to be reborn from the ashes. As well as humans, we tend to cyclically destroy ourselves and our societies only to build them up again. Granger hopes that eventually, men will learn the lessons from history and stop destroying society.
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24. what is the relationship between the number of bonds between two atoms and bond strength? bond length?
The strength of the bond describes how closely each atom is connected to another atom and how much energy is required to break that connection. The bond length is the average distance between the two atomic nuclei of two molecules that are joined together.
Define bond strength:The strength of the bond indicates how strongly each atom is bound to another and how much energy is expended in doing so. The force that a chemical bond utilizes to hold two atoms together is known as bond strength. The amount of energy required to break the bond is expressed in terms of the kilocalories per mole.
Define bond length:The equilibrium separation between the nuclei of two bound atoms in a molecule is referred to as the bond length. The bond length increases with increasing atom size. Bond multiplicity cause decrease in bond length. Rotational spectroscopy, X-ray diffraction, and other methods are used to measure it.
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Please help with the question!
Subtract the initial mass from final mass, i.e., vm.
given that the principal quantum number is n, the number of orbitals in each principal energy level is given by the expression .
The formula 2n², where n is the primary energy level, can be used to calculate the maximum amount of electrons in each energy level (first quantum number).
Where are the orbitals?The nucleus is the center of the orbits. One orbital will be larger than the others if an atom has several orbitals, or they will overlap. Additionally, an atom is perhaps most likely to occur in the electron shells. Orbitals, or groups of electrons arranged in a cloudlike pattern, surround the nucleus.
What shape do orbitals take?The highest level of probability for an electron to exist is in an atom's nucleus. The route that electrons travel while navigating the restrictions of the circle is referred to as a subshell. There are four different subshell classifications. The letters s, p, d, & f are used to identify the such.
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standard light antarctic precipitation (slap) is a common reference material when making hydrogen isotope measurements. analysis of slap shows that it is 0.008917% 2h (mass 2.01410 amu) and the remainder is 1h (mass 1.00782 amu). what is the average mass of slap?
so we have to calculate the average mass of the SLAP
given,
percentage abundance of 2H= 0.008917%
mass of 2H= 2.01410 amu
mass of 1H= 1.00782 amu
now we calculate, the percentage abundance of 1H = 100% - 0.008917%
= 99.991%
the average mass of SLAP = percentage abundance of 1H x mass of 1H + percentage abundance of 2H x mass of 2H
= 99.991% x 1.00782 + 0.008917% x 2.01410
=(99.991x1.00782)/ 100 +( 0.008917)x2.01410/100
= 1.00773 + 0.000173
= 1.0079 amu
the average mass of SLAP is 1.0079 amu
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a 20 ml sample of gastric juice (composed of strong acid) was titrated with 0.0011 m aqueous naoh. the addition of 6.7 ml of naoh resulted in a neutral ph. what was the original ph of the gastric juice sample?
The original pH of the gastric juice sample is 3.43
What is pH ?pH serves as a measure to calculate the acidity/alkalinity of a solution. It's ranges is between 0 - 14, with 7 being neutral. A pH below 7 indicates acidity and a pH above 7 indicates basicity. pH is actually a measure of the relative amounts of free hydrogen and hydroxyl ions in water.
As we know:
M₁V₁ = M₂V₂
For the given question:
M₁ = Concentration of gastric juice
V₁ = Volume of gastric juice (20 ml)
M₂ = Concentration of NaOH (0.0011 M)
V₂ = Volume of NaOH (6.7 ml)
So, M₁ = M₂V₂ / V₁
M₁ = 0.0011 × 6.7/20
M₁ = 0.000365
For pH:
pH = -log [H⁺]
pH = -log [0.000365]
pH = 3.43
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a 1.00 l solution contains 24.52 g of nitrous acid, hno2. what mass of sodium nitrite, nano2, should be added to it to make a buffer with a ph of 3.46? ka (hno2)
26.21g NaNO₂ is added to it to make a buffer with a pH of 3.46.
Describe buffer solution.A buffer solution's pH will not change when a small amount of an acid or an alkali is added.
A buffer solution that is acidic has a pH lower than 7, to put it simply. Acidic buffer solutions are usually made by mixing a weak acid with one of its salts, usually sodium salt.
A buffer solution with an alkaline pH exceeds 7. Alkaline buffer solutions are often made by mixing a weak base with one of its salts.
moles of HNO₂ = 24.52g HNO₂ ×[tex]\frac{1 mol HNO2}{47.013gHNO2}[/tex]
moles of HNO₂ = 0.33 moles HNO₂
pKa for HNO₂,
pKa = -log(Ka)
pKa = -log(4.0 × 10⁻⁴)
pKa = 3.39
Now, By using the Henderson-Hasselbach equation: determine the moles of NaNO₂.
Hence, both compounds (Weak base and acid) have same volume.
also use moles instead of concentrations:
pH = pKa + log ( [tex]\frac{moles NaNO2}{moles HNO2}[/tex])
moles of NaNO₂ = moles of HNO₂ × 10[tex]^{pH-pKa}[/tex]
moles of NaNO₂ = 0.33 moles × 10³°4⁶⁻³°³⁹
moles of NaNO₂ = 0.38 moles
moles of NaNO₂ to grams of NaNO₂,
= 0.38 × (68.99/1)
= 26.21g NaNO₂
amount of NaNO₂ is 26.21g.
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a piece of wood is measured and 1/4 of its 14c has decayed into 14n. approximately how old is it? (note: the half-life of 14c is 5,730 years.) a. 5,730 years b. 2,865 years c. 11, 460 years d. 50,000 years
A piece of wood is measured and 1/4 of its 14c has decayed into 14n. The half-life of 14c is 5,730 years. Approximately 5,730 years old is it.
What is Half-Life ?The half-life is the time required for a quantity to fall to half of its starting value. The expression is commonly used in nuclear physics to describe how quickly unstable atoms decay radioactively or how long stable atoms remain. The term can also be used more generally to refer to any type of exponential decay.
A measurement of a piece of wood reveals that one-fourth of its 14c has converted to 14n.
With a half-life of 5700 30 years, radiocarbon (14C) is particularly useful for dating in archaeology. The Gamow-Teller ß-decay, an uncommon impediment to the beta decay of 14C to 14N, causes this half-life to be short.
Radiocarbon dating, also referred to as carbon-14 dating, is a method of radiometric dating. It uses the naturally occurring radioisotope carbon-14 (14C) to estimate the age of items containing carbon up to a maximum of 58,000–62,000 years. Carbon has two stable, nonradioactive isotopes: carbon-12 and carbon-13. On Earth, trace amounts of the unstable radioactive carbon-14 (14C) are also present. Carbon-14 has an extremely short half-life of 5,730 years due to radioactive decay to nitrogen-14, which means that within this time, the percentage of carbon-14 in a sample will have dropped by 50%. Carbon-14 would vanish from Earth's atmosphere in less than a million years if it weren't for cosmic rays that are continually pelting the stratosphere and interacting with nitrogen molecules (N2) and single nitrogen atoms.
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A block and tackle is a rope and pulley system that uses multiple pulleys. It multiplies a small force into a large one. If a motor has a weight of about 2500 N and people pull 4.0 m of rope with a force of 700 N to raise the motor 1.0 m, how efficient is the block and tackle?
The efficiency of the machine is obtained as 89.3%.
What is a pulley?A pulley is one of the types of simple machine. We know that a simple machine has to do with anything that helps you to be able to do your work more efficiently.
We know that the efficiency has to do with how well the pulley is able to do work as we know. In this case we know that the efficiency is obtained from;
Work output/Work input * 100/1
Work output =2500 N * 1.0 m = 2500 J
Work in put = 700 N * 4 m= 2800 J
Efficiency = 2500 J/2800 * 100/1
= 89.3%
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calculate the ph of a buffer solution obtained by dissolving 29.029.0 g of kh2po4(s)kh2po4(s) and 44.044.0 g of na2hpo4(s)na2hpo4(s) in water and then diluting to 1.00 l.
The pH of buffer solution obtained will be 7.05 by dissolving 29.029.0 g of kh2po4(s)kh2po4(s) and 44.044.0 g of na2hpo4(s)na2hpo4(s) in water and then diluting to 1.00 l.
This can be calculated using use Henderson - Hasselbalch equation:
PH = Pka + ㏒ [A/AH]
Molar mass of KH₂PO₄ = 136.0 g And Molar mass of Na₂HPO₄ = 142.0 g
No. of moles of H₂PO₄⁻ = No. of moles of KH₂PO₄ = (29..0 g) / (136.0 g/mol) = 0.213 mol
No. of moles of HPO₄²⁻ = No. of moles of Na₂HPO₄ = (44.0 g) / (142.0 g/mol) = 0.30 mol
In the solution, [HPO₄²⁻]/[H₂PO₄⁻] = 0.213/0.30
Henderson-Hasselbalch equation:
pH = pKₐ + log([HPO₄²⁻]/[H₂PO₄⁻])
pH = 7.21 + log(0.213/0.30)
pH = 7.05
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by using photons of specific wavelengths, chemists can dissociate gaseous hi to produce h atoms with certain speeds. when hi dissociates, the h atoms move away rapidly, whereas the heavier i atoms move more slowly. if a photon of 248 nm is used, what is the excess energy (in j) over that needed for dissociation? enter your answer in scientific notation.
The excess energy needed for the dissociation of the HI atom is 3.102 x 10⁻¹⁹ J
The wavelength of the photons used to dissociate the HI molecule is 248 nm.
The energy of the photon is given by,
E = hc/λ
Where,
H is Planck's constant,
c is the speed of light,
λ is the wavelength of the photon,
Putting values,
E = 6.62 x 10⁻³⁴ 3 x 10⁸/248 x 10⁻⁹
E = 8 x 10⁻¹⁹ J.
The bond energy required to dissociate the HI atom is 4.898 x 10⁻¹⁹ Joules.
The excess energy is given by,
E = 8 x 10⁻¹⁹ - 4.898 x 10⁻¹⁹
E = 3.102 x 10⁻¹⁹ J.
so, the excess energy needed is 3.102 x 10⁻¹⁹ J.
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how many ml of propyl alcohol are required to make a 9.17% (v/v) aqueous solution in a 250. ml volumetric flask?
2,726.28 mL solution of propyl alcohol is required to make a 9.17% (v/v) aqueous solution in a 250. ml.
A solution's volume-by-volume percent concentration,
9.17% v/v is a measure of how many milliliters of solute it contains in 100 mL of solution.
In this case,
9.17% v/v solution will contain -
9.17 mL of solute for every 100 mL of solution.
This means that in order to have propyl alcohol required to make a 9.17% (v/v) aqueous solution in 250 ml of solute, you need to have
250 mL solute× 100 mL solution/ 9.17mL solute
=2,726.28 mL solution.
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