Respuesta :
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
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 :
[tex]\text{Molarity}=\frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (in L)}}[/tex]
In this question, the solute is NaCl.
Now put all the given values in this formula, we get:
[tex]0.020M=\frac{\text{Mass of solute}\times 1000}{58.44g/mole\times 350mL}[/tex]
[tex]\text{Mass of solute}=0.41g[/tex]
Therefore, the mass of NaCl present in solution are 0.41 grams.