# Chemistry

posted by .

For the reaction system, 2 H2O(g) + O2(g) == 2 H2O2 (g), the equilibrium concentrations are
(H2O2) = 0.120 M; (H2O) = 0.860 M; (O2) = 0.330 M.
Calculate the value of Kc for this reaction.

A. 0.423
B. 0.872
C. 0.0590
D. 1.31
E. 2.51

I did 0.120 / 0.860 X 0.330 = 4.4228 = 4.23.

Did I do this correctly?

• Chemistry -

You didn't balance the equation and you didn't make the coefficients the exponents.

• Chemistry -

To balance the equation would I add a 2 in front of the O2?

• Chemistry -

To know if it balances or not, count the atoms and see. You don't need to ask anyone. You want to put a 2 for O2?
2H2O + 2O2 ==> H2O2.

I see 4 H atoms on the left. I see 2 on the right. Equation isn't balanced.

• Chemistry -

so then 4.

• Chemistry -

2H2O + 4O2 ==> H2O2
I see 4 H atoms on the left and 2 on the right. Equation isn't balanced. Quit guessing and count the atoms. Try a value and count. It's that simple.

## Similar Questions

1. ### Chemistry

Hydrogen peroxide, H2O2, is a colorless liquid whose solutions are used as a bleach and an antiseptic. H2O2 can be prepared in a process whose overall change is the following. H2(g) + O2(g) H2O2(l) Calculate the enthalpy change using …
2. ### chemistry

A mixture of hydrogen peroxide, H2O2, and hydrazine, N2H4, can be used as a rocket propellant. The reaction is: 7 H2O2(g) + N2H4(l) ® 2 HNO3(aq) + 8 H2O(l) a) How many moles of H2O2 react with 0.477 mol N2H4?
3. ### chemistry

1. The bombardier beetle uses an explosive discharge as a defensive measure. The chemical reaction involved is the oxidation of hydroquinone by hydrogen peroxide to produce quinine and water: C6H4(OH)2 (aq) + H2O2 (aq) …
4. ### chemistry

Given: H2 (g) + O2 (g) ⇌ H2O2 (g) K = 2.3 x 106 at 600 K 2 H2 (g) + O2 (g) ⇌ 2 H2O (g) K = 1.8 x 1037 at 600 K Calculate Gº for the following reaction: H2O (g) + 1/2 O2 (g) ⇌ H2O2 (g)
5. ### chemistry-help!

The initial rate of reaction for H2O2(aq) <-> H2O (l) 1/2 O2 (g) is found to be 1.7x10(-3)M/s. Assume that this rate holds for 2 minutes. Start with 160ml of 1.60 M H2O2. How many milliliters of O2 measured at 24C and 760mmHg …
6. ### Chemistry

The Kc for the following reaction at 940oC is 1.38. Given the concentrations [CO2] = 0.500 M, [H2] = 0.425 M, [CO] = 0.610 M and [H2O] = 0.695 M, one can conclude that: H2(g) + CO2(g) ↔ CO(g) + H2O(g) Question 8 options: A) the …
7. ### Chemistry

Enthalpy changes: H2O2(l) ----> H2O(l) + 1/2P2(g) delta H= -94.6kJ H2(g) + 1/2O2(g)----> H2O2 delta H= -286.0kJ Calculate the value on delta H for the reaction: H2(g) + H2O2(l)----> 2H2O(l)
8. ### chem- i reallyneed help

Consider the following equations. N2H4(l) + O2(g) N2(g) + 2 H2O(l) ÄH = -622.2 kJ H2(g) + 1/2 O2(g) H2O(l) ÄH = -258.5 kJ H2(g) + O2(g) H2O2(l) ÄH = -187.8 kJ Use this information to calculate the enthalpy change for the reaction …