Question

1. Calculate the number of moles of carbon dioxide formed when 40.0 moles of oxygen is consumed in the burning of propane. Note the equation is unbalanced.
C3H8 + O2 ---> CO2 + H2O

a. 40.0 mol CO2
b. 42.0 mol CO2
c. 20.0 mol CO2
d. 24.0 mol CO2


2. Iron reacts with superheated steam to form hydrogen gas and the oxide Fe3O4. Calculate the number of moles of hydrogen produced by 10.0 g of iron and enough steam.

3Fe (s) + 4H2O (g) ---> Fe3O4 (s) + 4H2 (g)

a. 0.239 mol H2
b. 239 mol H2
c. 2.39 mol H2
d. 2239 mol H2


3. Iron (III) oxide, also known as rust can be removed from iron by reacting it with hydrochloric acid to produce iron (III) chloride and water.


Fe2O3 (s) + 6HCl (aq) ---> 2FeCl3 + 3H2O (l)

What mass of hydrogen chloride is required to react with 100 g of rust?

a. 371g HCl
b. 137g HCl
c. 130g HCl
d. 147g HCl


4. Calculate the number of grams of solid aluminium chloride that will form when a mixture containing 0.150 g of aluminum powder and 1.00 g of chlorine gas is allowed to react.

2Al (s) + 3Cl2 (g) ---> 2AlCl3 (s)

a. 741 g AlCl3
b. 471 g AlCl3
c. 0.741 g AlCl3
d. 246 g AlCl3


5. Balance the equation and state the limiting reagent in the following reaction:

Al (s) + Cl2 (g) ---> AlCl3 (s)
a. Chlorine
b. Aluminum
c. Aluminum chloride
d. None of the above


6. According to the collision theory, as the pressure increases, the rate of reaction will
a. Remain the same
b. Decrease
c. Increase
d. None of the above


7. Rate of reaction and temperature are ______________.
a. Inversely proportional
b. Directly proportional
c. Not related
d. Both a and b


8. Dynamic equilibrium occurs when
a. the chemical reaction continues to proceed, but the amount of reactants decrease.
b. the chemical reaction stops completely
c. the chemical reaction continues to proceed and the amount of product increases
d. the chemical reaction continues to proceed, but the amount of products and reactants remain constant


9. The addition of a ____________ increases the rate of reaction by providing an alternative pathway with a lower activation energy.
a. Catalyst
b. Acid
c. Base
d. All of the above


10. Which of the following dissociates in water to form the lowest concentration of H+
a. HCl (aq)
b. H2SO4 (aq)
c. HBr (aq)
d. H2CO3 (aq)


11. According to Arrhenius, an acid is a substance that increases the ____________ ion concentration in water.
a. Hydroxide
b. Hydronium
c. Potassium
d. Magnesium


12. A substance has a pH of 7.34. It is considered a
a. Base
b. Acid
c. Amphoteric
d. All of the above


13. Which group of acids listed completely dissociates in water?
a. HCl, H2SO4, HNO3
b. HCl, H2SO4, CH3COOH
c. HCl, H2SO4, H2CO3
d. HBr, H3PO4, H2CO3


14. Which group below correctly list bases that completely dissociate in water?
a. NaOH, KOH, LiOH
b. NH3, NH4OH, HCl
c. NaOH, H3PO4, MgOH
d. NaOH, KOH, H2CO3


15. When the oxidation number increases the element is ____________ and if the oxidation number decreases the element is ____________.
a. reduced, reduced
b. reduced, oxidized
c. oxidized, oxidized
d. oxidized, reduced


16. The oxidation number for O in NaHCO3 is
a. 1-
b. 1+
c. 2-
d. 2+


17. The oxidation number for Na, Cr, and O respectively in the compound Na2CrO4
a. 6+, 1+, 2+
b. 1+, 6+, 2-
c. 2-, 1+, 6+
d. 1-, 2-, 3+


18. CuSO4 + 2NaOH --> Cu(OH)2 + Na2SO4

The reaction above represents
a. Oxidation
b. Reduction
c. Neutralization
d. None of the above


19. A balloon with a volume of 5.0 L is filled with a gas at 2 atmospheres. If the pressure is reduced to 1 atmospheres without a change in temperature, what would be the volume of the balloon?
a. 5.0 L
b. 10 L
c. 12 L
d. 10 ml


20. A 700 mL sample of nitrogen is heated from 37 °C to 77 °C at constant pressure. What is the final volume?
a. 790 L
b. 790 ml
c. 970 ml
d. 970 L


21. A 8.0 L sample at 25 °C and 1.00 atm of pressure contains 0.5 moles of a gas. If an additional 0.75 moles of gas at the same pressure and temperature are added, what is the final total volume of the gas?
a. 20 L
b. 20 ml
c. 30 L
d. 25.5 L


22. 7.2 liters of an ideal gas are contained at 4.0 atm and 27 °C. Using the ideal gas law, calculate how many moles of this gas are present.
a. 22 mol
b. 1.2 L
c. 2.1 mol
d. 1.2 mo

Answer 1

Answer:

1. D (24.0 moles CO2)

2. A (.239 moles H2)

Explanation:

1. First Balance the equation

1 C3H8 + 5 O2 ---> 3 CO2 + 4 H2O

Then set up a stoiciometric equation so that the moles of O2 cancel out

40mol O2 x $\frac{3 mole CO2}{5 mole O2}$ = 24.0 moles CO2

2. Set up a stoichiometric equation

10 grams Fe x $\frac{1 mole Fe}{55.85 grams Fe}$ x $\frac{4 mole H2}{3 mole Fe}$ = 0.239 moles H2