To prepare 300.0 ml of 0.2 m nacl how many grams of nacl should be weighed out

Molar mass NaCl = 58.44 g/mol

Volume = 300.0 mL / 1000 => 0.3 L

number of moles:

1 L 0.2 M
0.3 L moles ?

moles = 0.3 x 0.2 / 1 => 0.06 moles of NaCl

Mass of NaCl:

1 mole NaCl 58.44 g
0.06 moles NaCl mass 

mass = 0.06 x 58.44 => 3.5064 g of NaCl