Question

2. Write a balanced chemical equation for the reaction of one anion in each of the categories in question 1.

A. a precipitation reaction

B. a redox reaction

C. an acid-base reaction

D. a gas-forming reaction

The Equations Given:

Ca+2(aq) + SO4 -2(aq) ↔ CaSO4(s) Equation 1

Ca+2(aq) + CO3 -2(aq) ↔ CaCO3(s) Equation 2

CaCO3(s) + 2H+ (aq) → Ca+2(aq) + CO2(g) + H2O(l) Equation 3

CaSO4(s) + H+ (aq) → No Reaction (precipitate remains) Equation 4

2NO2 - (aq) → NO(aq) + NO3 - (aq) Equation 5

2NO(g) (colorless) + O2(g) → 2NO2 (g) (red-brown) Equation 6

Ag+ (aq) + Cl- (aq) ↔ AgCl(s) Equation 7

Ag+ (aq) + Br- (aq) ↔ AgBr(s) Equation 8

Ag+ (aq) + I - (aq) ↔ AgI(s) Equation 9

Cl2(aq) (colorless) + Cl- (aq) (colorless) → No Reaction Equation 10

Cl2(aq) (colorless) + Br- (aq) (colorless) → Br2(aq) (yellow to brown ) + Cl- (aq) (colorless) Equation 11

Cl2(aq) (colorless) + I - (aq) (colorless) → I2(aq) (yellow to brown) + Cl- (aq) (colorless) Equation 12

NO3 - (aq) + 4H+ (aq) + 3Fe2+(aq) → NO(aq) + 3Fe3+(aq) + 2H2O(l) Equation 13

2NO(g) (colorless) + O2(g) → 2NO2(g) (red-brown) Equation 14

Answer 1

Ca+2(aq) + SO4 -2(aq) ↔ CaSO4(s) --------> precipitation reaction

Ca+2(aq) + CO3 -2(aq) ↔ CaCO3(s) --------> precipitation reaction

CaCO3(s) + 2H+ (aq) → Ca+2(aq) + CO2(g) + H2O(l) --------> Gas forming reaction

CaSO4(s) + H+ (aq) → No Reaction (precipitate remains) -----> None

2NO2 - (aq) → NO(aq) + NO3 - (aq) -----> redox reaction

2NO(g) (colorless) + O2(g) → 2NO2 (g) (red-brown) ------> Gas forming reaction

Ag+ (aq) + Cl- (aq) ↔ AgCl(s) ----------> precipitation reaction

Ag+ (aq) + Br- (aq) ↔ AgBr(s) --------> Precipitation reaction

Ag+ (aq) + I - (aq) ↔ AgI(s) --------> precipitation reaction

Cl2(aq) (colorless) + Cl- (aq) (colorless) → No Reaction

Cl2(aq) (colorless) + Br- (aq) (colorless) → Br2(aq) (yellow to brown ) + Cl- (aq) (colorless) ----> redox reaction

Cl2(aq) (colorless) + I - (aq) (colorless) → I2(aq) + Cl- (aq) ----> redox reaction

NO3 - (aq) + 4H+ (aq) + 3Fe2+(aq) → NO(aq) + 3Fe3+(aq) + 2H2O(l) -------> redox reaction

2NO(g) + O2(g) → 2NO2(g) -------> redox reaction

Note :

When both oxidation & reduction reaction takes place it is redox reaction.