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Many chemistry questions, acid and bases, stoichiometry

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Note:
1. Please clearly show all steps of logical solutions.
2. Be sure to give answers correct units and significant figures.

1.True or false
A. All compounds that contain hydrogen are acids.
B. A solution with pH 5 has 10 times higher [H+] than a solution with
pH 6.
C. SO3 in the atmosphere is one cause of acid rain.
D. Agricultural fertilizers are not a cause of water pollution.
E. One function of an auto catalytic converter is to convert CO
to CO2
F. In two half lives a radioactive isotope is completely gone.
G Beta radiation from an atom is emission of a valence electron.
H. In the same size container at the same temperature, 25g of N2 gas
Has the same pressure as 25g of NH3 gas.
I. Chlorofluorocarbon compounds are considered to be a prime cause
of ozone depletion in the stratosphere..
J. The two elements in greatest amount in air are N2 and O2 .

2. A water solution has 1.00x10-3 moles of H+ in 10.0L of solution.
A. What is the [H+] ?
B. What is the pH ?
C. What is [OH-] ?
D.Is the solution acidic or basic?

3. Explaining the reasons for your answers:
A. Why is a solution of SO3 in water acidic?
B. Why is a solution of MgO in water basic?

4. A. An isotope with atomic number 89 and mass number 225 emits an alpha
particle. What are the atomic and mass numbers of the resultant atom?
B. An isotope with atomic number 74 and a mass number of 188 emits a beta particle. What are the atomic and mass numbers of the resultant atom?

5. What is the pressure in atmospheres of 125 grams of N2 gas in a 12.0L container at 25.0oC ?

6. Why is HCl termed a "strong acid" and CH3COOH termed a "weak" acid?

7. How many grams of NaOH are contained in 825mL of a 0.400 molar solution?

8. 2C8H18 + 25O2 ? 16CO2 + 18H2O
How many liters of CO2 gas result at 0.950atm and 25.0oC when 525g of C8H18 react ?

9. Person A has well water with 0.011ppm (parts per million) of Pb2+ Person B has well water with 6.5x10-5 grams of Pb2+ in 5.00L
Which person has well water with the lower concentration of Pb2+ ? Clearly explain the reason for your answer.

10. 975 atoms of an element with a half life of 4.50 seconds are synthesized. How many of the atoms remain
A. After 9.00 seconds?
B. After 13.50 seconds?

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https://brainmass.com/chemistry/stoichiometry/many-chemistry-questions-acid-and-bases-stoichiometry-491842

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1.True or false

A. All compounds that contain hydrogen are acids.
---FALSE, because you can name a litany of compounds with hydrogen (methane, water, etc) that are not particularly acidic

B.  A solution with pH 5 has 10 times higher [H+] than a solution with pH 6.
--TRUE, pH is a log scale, so every point is a 10-fold change in H+ concentration

C.  SO3 in the atmosphere is one cause of acid rain.
--TRUE, SO3 can react with water to form sulfuric acid in weak concentrations

D.  Agricultural fertilizers are not a cause of water pollution.
--FALSE, The nitrates in the fertilizers can leach out with the rain and flow into water sources if not applied carefully

E.  One function of an auto catalytic converter is to convert CO
                        to CO2
--TRUE

F.  In two half lives a radioactive isotope is completely gone.
--FALSE, Two half-lives would reduce the amount of isotope to 1/4 the original amount

G  Beta radiation from an atom is emission of a valence electron.
--TRUE

H. In the same size container at the same temperature, 25g of N2 gas
     Has the same pressure as 25g of NH3 gas.
--FALSE, 25g of N2 is a little less than 1 mol, while 25g of NH3 is nearly 2 moles of gas, so the amounts in molar terms are different

I.  Chlorofluorocarbon compounds are considered to be a prime cause
                      of ozone depletion in the stratosphere.. 
--TRUE, this is why CFCs are not regularly used as refrigerants any longer

J.  The two elements in greatest amount in air are N2 and O2 .
--TRUE taken together O2 and N2 occupy more than 98% of all gas in the atmosphere

 2.    A water solution has 1.00x10-3 moles of H+ in 10.0L of solution.
                   A. What is the [H+] ?  
1.00x10^-3 mol in 10 L is 1.00x10^-4M
B. What is the pH ? 
-log[H+]=pH
-log(1e-4) =4
pH=4
C. What is [OH-] ?
pH+pOH = 14
4+pOH=14
pOH=10
-log[OH-] = pOH=10
Solve for OH-
[OH-] = ...

Solution Summary

This problem contains the answers to 15 stoichiometry and acid/base problems as well as 10 true and false questions pertaining to chemistry concepts. Clear explanations are delivered for most of the true/false problems, and all math is given in step-by-step detail. If any of these questions is giving you trouble, be sure to download this solution for some expert help!

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Problem Set - Help setting up

1 How many grams of oxygen are required to fill a 4.5 x 103 liter hyperbaric chamber at a pressure of 225 cm Hg and 62 F? If the same quantity of oxygen, was pumped back into a gas cylinder at a pressure of 200 atm and at 75 F, what would the volume be?

2 Any number of green plants can photosynthesize glucose (C6H12O6) in the presence of carbon dioxide and water, and producing oxygen as the remaining product. 250 ml of oxygen was produced. The oxygen was collected over water at 27C and at a pressure of 755 Torr. The vapor pressure of water at 27C is approximately 26mm Hg. What mass of glucose was produce? How many grams of water were used in this biosynthesis?

3 The solubility of laughing gas, dinitrogen monoxide, in water is 7.50 mg per cent by mass at 760 Torr and 25C. If the density of the resulting solution is 1.01 grams per milliliter, what is the morality of the resulting solution? What is the % of the volume?

4 The specific heat of fusion of silver is 25.0 calories per gram and the specific heat of silver is 0.25 Joules per gram per degree C. Calculate the energy required to melt 1.0 moles of silver if it starts as a solid at 25 C below its normal melting point and is heated to its normal melting point.

5 One of the methods for the determination of lead is the titration of lead solutions with a standardized potassium chromate solution. If 42.50 ml of a solution of 6.357 grams of potassium chromate per liter was used to completely react with a sample of 10.000 grams of a soluble lead salt, what is the percentage of lead in the sample?

6 To examine the soda fountain methods of making carbonated beverages by measuring the amount of acid in a fixed volume of Coca-Cola. Use a 250 ml sample for all analysis and make each batch with a separate CO2 cylinder so that the carbon dioxide content in each batch would be as uniform as possible. In a typical experiment, saturate the Coke solution with all the CO2 in the cylinder. Titrate the 250 ml sample of a phenolphthalein endpoint with 7.65 ml of a sodium hydroxide solution that contains 5.670 grams of sodium hydroxide per liter. How much carbon dioxide was in the saturated solution?

7 In the reaction of copper with concentrated nitric acid, the products are copper (II) nitrate, water and nitrogen monoxide, sometimes called nitric oxide. If 150 ml of nitric oxide were collected over mercury at 42C and under a pressure of 74.5 cm of mercury, how many grams of copper had reacted?

8 If all the nitric oxide from above problem was allowed to react with oxygen, a red-brow gas, nitrogen dioxide is formed. How many grams of nitrogen dioxide would be formed? How many oxygen molecules would be needed for this reaction?

9 Consider the carbon dioxide cylinder mentioned in problem 6 above. If the cylinder contains 27.35 grams of carbon dioxide, what volume would the gas occupy at 360 Torr and 850F?

10 Ammonia and gaseous hydrogen chloride combine to form ammonium chloride. If 4.21 liters of ammonia at 27C and 1.02 atm is combined with 5.35liters of hydrogen chloride at 26C and 0.998 atm, what mass of ammonium chloride will be produced? Which gas is in excess?

11 A tank contains 3.0 moles of nitrogen, 2.0 moles of oxygen, 1.5 moles of helium, and 1.8 moles of carbon dioxide at 45C and under 1000 atm. Calculate the partial pressure of each gas in the mixture in Torrcellis.

12 A weather balloon is filled with 1.0 liter of helium at 23C and 1.0 atm. What volume does the balloon have when it has risen to a point in the atmosphere where the pressure is 200 Torr and the temperature is -31C?

Unbalanced equation
CaCO3(s) + H+ (aq) Ca+2 (aq) + H2O(l) + CO2 (g)
How many moles of CO2 (g), are collected at 60C and 774 Torr, are produced by the complete reaction of 10.0 grams of CaCO3 with acid? What volume does this wet CO2 occupy? What volume would the CO2 occupy at 774 Torr if a desiccant, a chemical dying agent, were added to remove water? The vapor pressure of water at 60C is 149 mm Hg.

How many grams of silicon tetraflouride, a gas, at room temperature, would fill the same volume as the occupied by 295 grams of carbon monoxide at 75C and 575 Torr?

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