Question

How many grams of nacl are present in 350 ml of 0.020 m nacl solution? (remember that 1 mole nacl = 58.44 g/mole.)

Answer 1

Answer : The mass of NaCl present in solution are 0.41 grams.

Explanation : Given,

Volume of solution = 350 mL

Molar mass of NaCl = 58.44 g/mole

Molarity of NaCl = 0.020 M

Molarity : It is defined as the number of moles of solute present in one liter of volume of solution.

Formula used :

`\text{Molarity}=\frac{\text{Mass of solute}* 1000}{\text{Molar mass of solute}* \text{Volume of solution (in L)}}`

In this question, the solute is NaCl.

Now put all the given values in this formula, we get:

`0.020M=\frac{\text{Mass of solute}* 1000}{58.44g/mole* 350mL}`

`\text{Mass of solute}=0.41g`

Therefore, the mass of NaCl present in solution are 0.41 grams.

Answer 2

There are a number of ways to express concentration of a solution. This includes molarity. Molarity is expressed as the number of moles of solute per volume of the solution. The mass of NaCl needed for the solution is calculated as follows:

0.020 M = 0.020 moles NaCl / L

amount in moles of solute = 0.020 moles NaCl / L x .350 L = 0.007 mol NaCl

amount in grams =0.007 mol NaCl x 58.44 g/mol = 0.41 g NaCl