QUATERLY 3 REVIEW- key

Chapter 12 – Stoichiometry

6. a. 537g Fe

b. 93.1g Fe

7. 14.7g of Ba3(PO4)2; Limiting reactant- Ba(NO3)2; Excess left over- 9.5g Na3PO4; 83.7% yield

Chapter 13 – Solids and Liquids

  1. dipole-dipole, dispersion
  2. dispersion
  3. dispersion
  4. H-bonds, dipole-dipole, dispersion
  5. Solids- definite shape/volume, organized & close, vibrate around fixed point. Liquids- definite volume, shape of container, unorganized yet close, move past each other.
  6. network
  7. metals
  8. molecular
  9. amorphous
  10. ionic
  11. strong IMF = low volatility, low vapor pressure, high bp
  12. 28.0 g/mol

Chapter 14 – Gases

  1. 1180 mmHg
  2. 180. kPa
  3. 493°C
  4. 80. L
  5. 440. L
  6. 43.6 g/mol
  7. 7.94 L
  8. 93.2 K

Chapter 15 – Solutions

  1. Unsaturated-dissolves, saturated-sinks to bottom, supersaturated-excess crystallizes
  2. temp↑ solubility solids ↑

solubility gases 

pressure ↑ solubility gases ↑

  1. soluble25. soluble
  2. insoluble26. insoluble
  1. a. 40 gramsc. CO2 downwards

b. ~7 grams

  1. 9.00 g
  2. 4.2 mL
  3. Molarity= mol solute/L of solution

Molality = mol solute/kg of solvent

  1. AlCl3
  2. Fp = -4.76°C, bp = 101.31°C

EXTRA PRACTICE PROBLEMS – key

  1. What relationships can be determined from a balanced chemical equation?

Mole to mole

  1. Explain why mole ratios are central to stoichiometric calculations.
    Since atoms and molecules have different masses, we need to compare moles to have the correct number of particles.

3. How many grams of silver phosphate are produced?
3AgNO3 + Na3PO4  Ag3PO4 + 3NaNO3


4a. Whatvolume of hydrogen at STP is produced from the reaction of 50.0 g of Mg and 75.0 g of HCl?
Mg + 2HCl  MgCl2 + H2



b. How much excess reactant is left over?

5. A balloon is filled with 3.0 L of helium at 1 atm. What is the volume when the balloon rises to an altitude where the pressure is only 0.25 atm? (assume temperature remains constant.)

= 12L

6. The gas left in a used aerosol can is at a pressure of 1 atm at 27°C. If this can is thrown into a fire, what is the internal pressure of the gas when its temperature reaches 927°C?

= 4 atm

7. 5.2 L of a gas is at STP. Find the new volume when the temperature rises to 38°C and the pressure drops to 600 mmHg.

8. Pressure and volume of a gas at constant temperature are __directly____ proportional. Which scientist said this? ___Boyle______

9. Volume and temperature of a gas at constant pressure are ___ directly ______proportional. Which scientist said this? _ Charles ______

10. Volume and number of gas particles at constant pressure and temperature are ___ directly ______proportional. Avagadro

11. If two containers are at the same temperature and pressure and their volumes are equal, they must contain the same ______# of particles____. Which scientist said this? ______Avagadro______

12. Which travels faster CO2 or O2? How much faster? O2, it travels 1.17x faster

13. Gas A travels 4 times faster than Gas B. If the molar mass of Gas B is 80 g/mole, find the molar mass of Gas A.
square both sides. 80/X=16 X=80/16 X=5 g/mol
14. a. 100°C

b. gas

c. vaporization

15. Ethylen glycol

16. At 1.0 atm , 0.75g of gas dissolves in 1L at 55 degrees. How much of the gas will dissolve in 1L at

4.0 atm at the same temperature? Who came up with this law?___Henry______
= 3g/L

17. What volume of 3.70 M solution can be prepared using 89.5 grams of sulfuric acid?
3.70M = 0.913moles H2SO4

X L solution =0.246L

18. What mass of magnesium chloride is required to prepare 2.15 liters of 6.50 M solution?
6.50M = X moles MgCl2 X = 14.0 moles MgCl2

2.15 L solution 14.0mole x 95.31g MgCl2 = 1330g (SF)

1 moleMgCl2

19. How would you prepare 2250.mL of a 3.250 M solution from a 16.00 M HNO3 stock solution?

M1V1 = M2V2 (16.00 M)(X mL) = (3.250 M)( 2250. mL) dilution!!!!!!!!!!!

Take 457.0mL of the stock solution (stronger) and add 1793 mL of water

20. If you mixed the following solutions, what would be the resulting molarity?

525 mL of 2.1M HCl

375 mL of 4.8 M HCl

295 mL of 7.6 M HCl

1195ml

21. Circle all solutes that an “i” factor of 1?

a. C6H12O6b. CF4c. NH4Cl (i=2)d. NH3

22. Why is calcium chloride more effective as rock salt in the winter than sodium chloride? (HINT: what is the “i” factor for each?)calcium chloride (CaCl2) has an i of 3. NaCl has an i of 2. Calcium chloride will lower the freezing point of water more.