Answer:
Mass of HCl leftover = 6.4 g
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
NaOH + HCl —> NaCl + H₂O
Next, we shall determine the masses of NaOH and HCl that reacted from the balanced equation. This can be obtained as follow:
Mass of NaOH = 23 + 16 + 1
= 40 g/mol
Mass of NaOH from the balanced equation = 1 × 40 = 40 g
Molar mass of HCl = 1 + 35.5 = 36.5 g/mol
Mass of HCl from the balanced equation = 1 × 36.5 = 36.5 g
SUMMARY:
From the balanced equation above,
40 g of NaOH reacted with 36.5 g of HCl.
Next, we shall determine the mass of HCl required to react with 7 g of NaOH. This can be obtained as follow:
From the balanced equation above,
40 g of NaOH reacted with 36.5 g of HCl.
Therefore, 7 g of NaOH will react with = (7 × 36.5)/40 = 6.4 g of HCl.
Thus, 6.4 g of HCl is required for the reaction.
Finally, we shall determine the leftover mass of HCl. This can be obtained as follow:
Mass of HCl given = 12.8 g
Mass of HCl that reacted = 6.4 g
Mass of HCl leftover =?
Mass of HCl leftover = (Mass of HCl given) – (Mass of HCl that reacted)
Mass of HCl leftover = 12.8 – 6.4
Mass of HCl leftover = 6.4 g