Calculate the mass of potassium iodide ki which is obtained by the interaction of 29.64 g of potassium with iodine I2?

Given:

m (K) = 29.64 g

To find:

m (KI) -?

Decision:

2K + I2 = 2KI, – we solve the problem using the equation of this chemical reaction:

1) Find the amount of potassium contained in 29.64 grams of the substance:

n (K) = m: M = 29.64 g: 39 g / mol = 0.76 mol;

2) We compose a logical expression:

if 2 mol K gives 2 mol KI,

then 0.76 mol K will give x mol KI,

then x = 0.76 mol.

3) Find the mass of potassium iodide formed during the reaction:

m (KI) = n * M = 0.76 mol * 166 g / mol = 126.16 g.

Answer: m (KI) = 126.16 g.