Some Chemistry Help: Am I right?

Question

1. Write a balanced equation for each of the reactions performed. Include the physical state of each substance. Classify each of the reactions as direct combination, decomposition, single replacement or double replacement.

Burning Mg:
2Mg(s) +02(g) > 2MgO (s) (? Type of Reaction)

Mg and HCl
Mg(s) + 2HCl(aq) >MgCl2(aq) + H2(g) (Single Replacement?)

Heating Cu
2Cu(s) +O2(g) > 2CuO(s) (? type of reaction)

H2O2 and MnO2
MnO2(s) + H2O2(aq)+2H(aq) > Mn2(aq) + O2(g) +2H2O (? Decomposition)

2KI + Pb(NO3)2 >PbI2 + 2KNO3 (? type of reaction)

2. Limewater is an aqueous solution of Ca(OH)2. Speculate on the identity of the cloudy white precipitate that forms with CO2 gas. Write a chemical equation for this reaction that is consistent with your observations.

3. A positive test for hydrogen was the "pop" test. What chemical reaction was occuribng? Write a balanced equations representing this reaction.

Answer 1

direct combination
single replacement
redox
decomp
double replacement

Ca(OH)2 (aq) + CO2 (g) → CaCO3 (s) + H2O (l)

2H + 2O2 → 2H2O direct combination

BTW, you will not learn properly for the next semester if you beg for answers. Chemistry, along with Math must be understood.

Answer 2

1.
Balanced correctly. Combination.
Balanced correctly. Yes.
Balanced correctly. Combination.
Balancing needs work. Yes, decomposition.
Balanced correctly. Double decomposition, metathesis.

2. Ca(OH)2(aq) + CO2(g) ===> CaCO3 + H2O

3. 2H2(g) + O2(g) ===> H2O(g)