When chlorine was passed through a potassium iodide solution, 2.54 g of iodine was formed

When chlorine was passed through a potassium iodide solution, 2.54 g of iodine was formed. Calculate the mass of potassium iodide in the original solution.

1. Chlorine in the group is higher than iodine, so it can displace it from salts, we write down the reaction equation:

Cl2 + 2KI = 2KCl + I2;

2.find the chemical amount of iodine:

n (I2) = m (I2): M (I2);

M (I2) = 2 * 127 = 254 g / mol;

n (I2) = 2.54: 254 = 0.01 mol;

3. go to the determination of the chemical amount of potassium iodide, according to the reaction equation in front of it coefficient 2, which is two times more than in front of iodine:

n (KI) = 2 * n (I2) = 2 * 0.01 = 0.02 mol;

4. find the mass of iodide:

m (KI) = n (KI) * M (KI);

M (KI) = 39 + 127 = 166 g / mol;

m (KI) = 0.02 * 166 = 3.32 g.

Answer: 3.32 g.