Calculate what mass of table salt is needed to prepare 500 ml of a 1 M solution of this salt; 1 L of a 2.5 M solution of this salt.

In one liter of solution, the salt concentration should be 1 mol / liter.
The amount of salt in 0.5 liters will be 1 x 0.5 = 0.5 mol;

Let’s find the mass of this amount of salt.

M NaCl = 23 + 35.5 = 58.5 grams / mol;

The salt mass will be:

m NaCl = 58.5 x 0.5 = 29.25 grams;

In one liter of solution, the salt concentration should be 2.5 mol / liter.
The amount of salt in 1 liter will be 1 x 2.5 = 2.5 mol;

Let’s find the mass of this amount of salt.

M NaCl = 23 + 35.5 = 58.5 grams / mol;

The salt mass will be:

m NaCl = 58.5 x 2.5 = 146.25 grams;