Answer: 6.58g
Explanation: We are to find the mass of NaCl that can produce 15% solution in a 750ml
STEP 1:
the reaction moles
NaCl + H2O = NaOH + HCl
Therefore 1mole of NaCl reacts with 1mole of H2O
STEP 2:
convert 750ml to liter
750ml × 1L/1000ml = 0.750L
STEP3 :
convert percentage concentration to mol/L
15% = 0.15mol/L
STEP 4:
find the mole
Mole= concentration× volume
0.15mol/L × 0.75L =0.1125mol
STEP 5 :
Find the mass
Mass = mole × molar mass
The molecular mass of NaCl is 23+35.5= 58.5g/mol
Therefore:
0.1125mol × 58.5g/mol = 6.58g
Approximately: 6.6g
