Unit 4 – Chemical Quantities

What are the molar masses (molecular weights) of the following compounds?

1)NaOH2)H3PO4

1)How many moles are in 15 grams of lithium?

1)How many grams are in 4.5 moles of sodium fluoride, NaF?

1)How many molecules (particles) are there in 24 grams of FeF3? Molar mass = 112.85 g/mol

1)What is the mass of 7.5 x 1023 molecules of H2SO4? Molar mass = 98.09 g/mol

1)How many liters are taken up by 122 grams of O2? Molar mass = 32.00 g/mol

2)What is the mass of 94 liters of H2? Molar mass = 2.02 g/mol

Calculate the percent composition of each of the following compounds:

  1. NaHSO4

What’s the empirical formula of a molecule containing 65.5% carbon, 5.5% hydrogen, and 29.0% oxygen?

What’s the molecular formula of a compound with an empirical formula of C4H4O and a molar mass of 136 grams per mole.

Unit 5 – Chemical Reactions

Write the formula equations for the following word equations.

Solid Magnesium Oxide decomposes to form Solid Magnesium and Oxygen Gas

Solid Sodium and Aqueous Calcium Fluoride React to for Solid Calcium and Aqueous Sodium Fluoride

Balance the following equations

__Fe + __O2 -> __Fe2O3

__H 2SO4 +__Pb(OH)4 -> __Pb(SO4)2 + __H2O

Give the reaction types and put an R below each reactant, and a P above each product.

PbCl2 + AgNO3 -> Pb(NO3)2 + AgCl

NH3 + HCl -> NH4Cl

State whether or not the following single replacement reactions will take place:

Zinc + Hydrogen chloride ->

Magnesium + Hydrogen Sulfate ->

Copper (II) chloride + Flourine ->

Silver + Sodium Hydroxide ->

Give the products for the following double replacement reactions, or write no reaction if no reaction:

Barium chloride + Aluminum sulfate

Calcium nitride + water

Identify whether the following processes are exothermic or endothermic:

  1. Less potential energy in products:
  1. ∆H = negative:
  1. Forming a bond:

Unit 6 Stoichiometry

Provide the mole ratios for the following equations:

  1. 3 CaCl2 + 2 Na3PO4 -> Ca3(PO4)2 + 6 NaCl
  2. 2 C4H10 + 13 O2 ---> 8 CO2 + 10 H2O
  1. How many moles of NaCl will be produced from 8.5 moles of Cl2?

2 NaBr + Cl2 -> 2 NaCl + Br2

  1. Given the following equation: 2 C4H10 + 13 O2 ---> 8 CO2 + 10 H2O How many grams of H2O is produced from 36 grams of O2?
  1. Given the following equation: 8 Fe + S8 ---> 8 FeS How many grams of Fe is needed to react with 16 moles of S8?
  1. Given the following equation: 2 C4H10 + 13 O2 ---> 8 CO2 + 10 H2O How many liters of CO2 is produced from 57 grams of O2?
  1. A 26 g sample of NaBr is mixed with 53 grams of Cl2. Determine the limiting reactant. 2 NaBr + Cl2 -> 2 NaCl + Br2
  1. A reaction was supposed to produce 6.9 L of NaCl. However it actually produced 3.8 L of NaCl. What is % yield?
  1. If you have a theoretical yield of 81 ounces, and you have a 62.1 % yield, then what was your actual yield?
  1. The table shows the mole ratio of Hydrogen and Oxygen combined to form water according to the balanced reaction 2H2 + O2 -> 2H2O. In which trial(s) is the amount of Oxygen the limiting reagent?

Trial Number / Moles of H2 / Moles of O2
1 / 10 / 3
2 / 3 / 2
3 / 14 / 8

Unit 7 Gas Laws

Combined Gas Law:

1250 mL of gas at 35 oC under 7.3 atm of pressure , are heated up to 68 oC and compressed to 757 mL. What is the final pressure?

726 mL of gas at 74 oC under 1.8 atm of pressure , are cooled down to 61 oC and released to 0.5 atm. What is the final volume?

525 mL of gas at 71 oC under 4.2 atm of pressure , are forced to 8.6 atm and compressed to 150 mL. What is the final temperature?

With an initial volume of V, if the temperature is doubled (while keeping Pressure constant), and then the pressure is divided by four (while keeping temperature constant, what is the final volume?

On the atomic level, why does pressure decrease with temperature?

If I have 2 moles of gas inside a sealed container, and then double the pressure, what happens to the number of moles?

For the graph below answer the following questions:

What happens to x as you decrease y?

Keeping y constant, what happens to x as you decrease z?

Keeping x constant what happens to y as you decrease x?

Unit 8 – Solutions, and Acids & Bases

Draw the solvation process labeling the charges, and having correction orientation:

1)How does the solvation process take place?

2)How are soluble and insoluble defined?

3)What is the molarity of 0.5 moles of HCL in 0.1 L of solution?

4)Give the qualities of acidic solutions:

5)Give the qualities of basic solutions:

6)Define Neutral Solution:

7)What determines the pH of an acid or base:

8)Write and balance the following neutralization reactions:

a)HCH3COO + AgOH ->

b)H3PO4 + Cr(OH)3 ->

Unit 9 – Kinetics, Equilibrium

9)According to Collision Model what two things are necessary for a reaction (formation of bonds) to occur?

a)

b)

10)Define Reversible Reaction:

11)Define Chemical Equilibrium and why is it dynamic:

12)Draw a vertical line at the point where chemical equilibrium is reached on the following graphs:

13)State what effect the following situations will have on the rate of reaction, and explain why:

a)The temperature is increased:

b)The reactants are crushed into a fine powder:

c)A catalyst is being used:

14)Explain which side of the reaction energy is on in the following reactions:

a)Exothermic reaction:

b)Endothermic reaction:

15)For the following problems explain which direction the equilibrium will shift, why it will shift that direction, and what will be produced?

a)N2(g) + 3H2↔ 2NH3(g) + Energy where we decrease the temperature

Equilibrium will shift to the _____ in order to ______thereby producing more ______.

b)C2H8(l) + O2(g)  CO2(g) + H2O(g) + Energy where we increase the temperature

Equilibrium will shift to the _____ in order to ______thereby producing more ______.