Please this is all i have left for this credit please please please chemistry / ohysics questions?

Question

1. rewrite the fallowing equation so its reversable

CaO ---> Ca ^2+ + 2 OH-

2. ocean water A. is highly acidic B. releases large amounts of disolved CO2 C. neutralizes carbonic acid

3. if substance A is reduced by substance B substance B is acting as A. a reducing agent B. an oxidizing agent C.a salt

D. none of these

4. when substance A is reduced by substance B, what happens to substance B? substance A acts on substance B as A. a reducing agent B.an oxidizing agent C. a salt D. none of these

Answer 1

1. CaO + H2O <----> Ca2+ + 2OH

(put the calcium oxide in solution)

2. B

3. A

4. B