Read the reaction and the statement. 2X(g) + Y2(g) ⇌ 2XY(s)

The equilibrium constant for the chemical reaction is found to be 20 at 150 K.

If the concentration of X is 4.0 × 10-2 M, what is the concentration of the Y2 gas?

5.50 M

8.0 M

31.25 M

40.0 M

[Y₂] = 31.25M

Explanation:

Based on the chemical reaction:

2X(g) + Y2(g) ⇌ 2XY(s)

We must define the equilibrium constant, K as:

K = 20 = 1 / [X]²[Y₂]

Where [X] and [Y₂] are the equilibrium concentrations of each gas.

If [X] = 4.0x10⁻²M:

20 = 1 / [4.0x10⁻²M]²[Y₂]

0.032 = 1 / [Y₂]

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles