1. the chemical symbol "ni" most likely represents:

a. antimony
b. lead incorrect
c. carbon
d. nickel

2. how do the products of chemical reactions compare to their reactants?

a. the products usually weigh more than the reactants
b. the products usually have more atoms than the reactants
c. the products often have completely different properties than the reactants
d. the products are usually more toxic than the reactants

3. what's the problem with this chemical equation: h2 + o2 = h2o?

a. there's an additional hydrogen in the reactants
b. there's a missing hydrogen in the reactants
c. there's a missing oxygen in the product
d. there's an additional oxygen in the product

4. what's the easiest way to balance a chemical equation?

a. complex algebra
b. calculus
c. using the periodic table
d. trial and error

5. which reactant is missing from the following equation? x + po4 ¬ h3po4?

a. one phosphorus atom
b. one oxygen atom
c. one hydrogen atom
d. three hydrogen atoms

6. what is the product of the following equation? 2na + s2o3 ¬?

a. nas4o3
b. na2s2o3
c. nas2o3