Chemistry Answers

one mole of an ideal gas is allowed to expand at 25 degree celsius till its pressure falls to one- fifth of its original pressure. find out the free energy

Draw the structure of phenolphthalein and methyl orange in neutral and their working pH range. Are they water soluble?

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