2.  Which of the following is an empirical formula? a. C 2 H 6 O 2 b. C 4 H 8 O 10 c. C 2 H 2 O 2 d. C 2 H 3 O 2

3.  What is the percent composition of Na2S? ▪ 58.90 % Na ▪ 41.10 % S

4.  How many moles of NH3 are produced if 25 moles of H2 React with N2?  N2 +3 H2 ―> 2 NH3 ▪ 25 mole H2 x 2 mole NH3 = 17 mole NH3 3 mole H2

5.  How many grams of water are produced from the reaction of 2.5 grams of oxygen with excess hydrogen?  2.5 g O2 x 1 mole O2 x 2 mole H2O x 18 g H2O 32 g O2 1 mole O2 1 mole H2O = 2.8 g O2

6. What is the limiting reactant in this reaction?

7. What is the excess reactant?

8. Which salt is most soluble at 10 ⁰ C?

9. Which salt is least soluble at 80 ⁰ C?

10. At 50 ⁰ C how much potassium dichromate will dissolve?

11. If there is 60 grams of potassium chloride dissolved in solution at 50 ⁰ C, what type of solution is it?

12. How much potassium nitrate will dissolve in 200g of water at 40 ⁰ C?

13. How much potassium chlorate will precipitate when the temperature is dropped from 70 ⁰ C to 30 ⁰ C

14.  What is the formula for: Copper(II) Nitrate?

15.  What happens to the pressure of a gas when the temperature is increased?

16.  What is STP?

17.  If there is one mole of gas at STP, what volume does it occupy?

18.  How do you get a substance to dissolve faster?

19.  If more solvent is added to a solution of 6.8 M hydrochloric acid, what happens to the concentration?

20.  If I mix 2.5 g of sodium carbonate with 100 ml of water, identify the solvent and solute of the solution and the concentration in molarity of the solution.

21.  What is the molarity of a solution when you add 250 mL of water to 50 mL of 3.0 M solution of sodium hydroxide.

22.  What type of reaction is:  2 NaCl ―> 2 Na + Cl2

23.  What type of reaction is:  CH4 + 2O2 ―> 2 H2O + CO2

24.  What are the diatomic elements?

25. What is this chart used for and how does it work?

26. According to the chart, will a reaction between Calcium metal and Aluminum nitrate occur?

27. According to the chart, which metal(s) will displace a solution of sodium nitrate?

28.  What is the formula for percent yield?

29.  How many moles of silver nitrate will react with 2.5 mole of Calcium Chloride? 2 AgNO3 + CaCl2 → 2 AgCl + Ca(NO3)2

30.  How many grams of silver chloride are needed to produce 10.5 grams of silver chloride? 2 AgNO3 + CaCl2 → 2 AgCl + Ca(NO3)2

31.  Balance the following reaction and identify the following terms:  ___H2SO4 + ___Ba(OH)2 ―> ▪ Coefficient ▪ Subscript ▪ Reactant ▪ Product ▪ Type of reaction