General Chemistry Answers

What is Waste bins

Can water stay liquid below zero degrees Celsius?

Are two atoms of the same element identical

What is the hydroxide ion concentration of a solution with a pH of 2.262

1. 5.47 x 10 ^-4
2. 1.83 x 10 ^-12
3. 1.83 x 10 ^-13
4. 5.47 x 10 ^-3
5. 1.83 x 10 ^-11
6. 5.47 x 10 ^-2

The solubility of lead(II) fluoride in water is 0.0175% (w/v) at 29°C. Calculate the K_sp of this salt at this temperature

1. 1.46 x 10^-12 M
2. 1.46 x 10^-9 M
3. 3.64 x 10^-10 M
4. 1.31 x 10^-9 M
5. 1.31 x 10^-12 M
6. 3.28 x 10^-10 M

Calculate the solubility of Ca(OH)₂ in a 0.469M CaCl₂ solution at 31°C, given that the K_sp of Ca(OH)₂ is 4.96 x 10^-6 at that temperature.

Give your answer in milli Molar units

1. 2.927 mM
2. 626 mM
3. 764 mM
4. 1.382 mM
5. 1.463 mM
6. 3.252 mM

For the equilibrium

H_2(g) + CO_{2(g) ↔} H₂O_(g) + CO_(g)

K_c = 3.180 at 1106K. If each of the four species was initially present at a concentration of 3.000 M, calculate the equilibrium concentration of the H2(g) at this temperature. Give your answer in units of mol/L

1. 1.832
2. 2.156
3. 0.844
4. 3.844
5. 1.940

A 4.30 L container had 33.40 moles of N₂O₄ added to it. When equilibrium was established, the concentration of NO₂ was found to be 2.67M. What is Kc for the following reaction

N₂O₄(g) ↔ 2NO₂(g)

1. 0.997 M
2. 0.415 M
3. 0.942 M
4. 0.374 M
5. 0.353 M
6. 1.108 M

The following reactions occur at 500 K. Arrange them in order of increasing tendency to proceed to completion (least to greatest tendency).

1. 2NOCl ↔ 2NO + Cl₂ Kc = 1.7 x 10^-2

2. 2SO_3 ↔ 2SO₂ + O₂ Kc = 1.3 x 10^-5

3. 2NO_2 ↔ 2NO + O₂ Kc = 5.9 x 10^-5

1. 2 < 1 < 3
2. 3 < 1 < 2
3. 3 < 2 < 1
4. 1 < 2 < 3
5. 2 < 3 < 1

Which is the correct equilibrium constant expression for the following reaction?

Fe₂O₃(s) + 3H₂(g) ↔ 2Fe(s) + 3H₂O(g)

1. K_c = [Fe₂O₃] [H₂]³ / [Fe] ² [H₂O] ³
2. K_c = [Fe] [H₂O] / [Fe₂O₃] [H₂]
3. K_c = [H₂] / [H₂O]
4. K_c =  [H₂O]³  / [H₂]³
5. K_c = [Fe] ² [H₂O] ³ / [Fe₂O₃] [H₂]³