2. How many grams of sodium fluoride (NaF) are needed to prepare a 0.400m NaF
solution that contains 750 g water? (molar mass of NaF - 42.0 g/mol)
20%
A 18.9 g NaF
OB 9.12 g NaF
c 12.6 g Naf
OD 28.0 g Naf

12.6 g NaF

Explanation:

Recall that 1g of water =1 ml of water hence the volume of the solution is 750ml

Given that

m/M= CV

m= mass of solute =

M= molar mass of solute= 42.0 g/mol

C= concentration of solution= 0.400 M

V=volume of solution= 750ml

m= MCV

m= 42.0g/mol × 0.400 M ×750/1000

m= 12.6 g of NaF

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock