Question

At STP, adding salt to a 200 mL sample of water produces a saturated 1.7 M solution. How many grams of salt (NaCl) must be added to 200 mL to produce this solution?

Answer 1

`m_(NaCl)=19.9gNaCl`

Step-by-step explanation:

Hello!

In this case, since the formula for the calculation of molarity is:

`M=(n)/(V)`

Whereas we can compute the moles of the solute as shown below, making sure the volume is in liters:

`n=M*V`

Thus, by plugging in we obtain:

`n=0.200L*1.70mol/L=0.170molNaCl`

Next, since the molar mass of NaCl is 58.44 g/mol, we obtain the following mass:

`m_(NaCl)=0.170molNaCl*(58.44gNaCl)/(1molNaCl)\\\\m_(NaCl)=19.9gNaCl`

Best regards!