Nitrosyl bromide decomposes according to the following equation.
2NOBr (g)(equilibrium arrow) 2NO (g) + Br2 (g)
A sample of NOBr (0.64 mol) was placed in a 1.00-L flask containing no NO or Br2. At equilibrium
the flask contained 0.46 mol of NOBr. How many moles of NO and Br2, respectively, are in the
flask at equilibrium?
A) 0.18, 0.18 B) 0.18, 0.090 C) 0.46, 0.46 D) 0.46, 0.23 E) 0.18, 0.360
i thought it was .18 .18 but i was wrong. how is this problem solved/
0.6 and 0.2 respectively
To solve this problem, we need to use the stoichiometry of the balanced chemical equation and the given information.
1) Start by writing the balanced chemical equation:
2NOBr (g) ⇌ 2NO (g) + Br2 (g)
2) Use the given information to determine the initial and equilibrium moles of NOBr:
Initial moles of NOBr = 0.64 mol
Equilibrium moles of NOBr = 0.46 mol
3) Set up an ICE table (Initial, Change, Equilibrium) to track the moles of each species:
2NOBr (g) ⇌ 2NO (g) + Br2 (g)
Initial: 0.64 0 0
Change: -x +2x +x
Equilibrium:0.64-x 2x x
4) Based on the stoichiometry of the balanced equation, we can see that for every 2 moles of NOBr that react, we get 2 moles of NO and 1 mole of Br2. Therefore, the moles of NO and Br2 formed at equilibrium are related by the equation: 2x = x.
5) Now, solve for x by using the equation derived in step 4:
2x = x
x = 0.46 mol
6) The moles of NO and Br2 at equilibrium are:
Moles of NO = 2x = 2 * 0.46 = 0.92 mol
Moles of Br2 = x = 0.46 mol
So, the correct answer is option D) 0.46, 0.23. At equilibrium, the flask contains 0.46 mol of NO and 0.23 mol of Br2.