Question

How many moles and how many grams of sodium chloride are present in 250 cm3vof a 0.5 NaCl solution

Answer 1

Molar mass of NaCl = 23 + 35.5 = 58.5 g
Volume of solution = 250 mL 
Molarity = 0.50 M
Molarity = Number of molesVolume in litres n = 0.5 ×0.25 = 0.125 molesn = Given massMolar massGiven mass = 0.125×58.5 = 7.3125 g

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