Aqueous hydrochloric acid will react with solid sodium hydroxide to produce aqueous sodium chloride and liquid water . Suppose 12.8 g of hydrochloric acid is mixed with 7.0 g of sodium hydroxide. Calculate the minimum mass of hydrochloric acid that could be left over by the chemical reaction. Round your answer to significant digits.

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