Question

Question #8af7e

Answer 1

`m_(NaCl)=394.2g`

Explanation:

The concentration is related to the mass through the number of mole:

`C_M=n/V`

and the number of mole is related to the mass by:

`n=m/(MM)`

Therefore, we can first calculate the number of mole from the concentration and the volume by:

`n=C_MxxV=4.50(mol)/(cancel(L))xx1.50cancel(L)=6.75mol`

Now from the number of mole we can find the mass by:

`m=nxxMM=6.75cancel(mol)xx58.4 g/(cancel(mol))=394.2g`

Thus we will need to weigh `394.2g` of `NaCl` and add it to `1.50L` of water to prepare `4.50M` solution of sodium chloride.

Here is a video that will show you how to prepare a solution in the lab:
Lab Demonstration | Solution Preparation & Dilution.