Chapter 1, Problem 47A

Interpretation Introduction

Interpretation:

Quantity of added acid to water needs to be determined.

Concept introduction:

An acid donates protons or hydrogen ions and/or accepts electrons in an aqueous solution. Water is a chemical compound consisting of two hydrogen atoms and one oxygen atom.

Answer to Problem 47A

The answer is $\text{2 mL}$.

Explanation of Solution

There is no strict rule on the units of measurement when the ratio is given in parts. It is a general term that is applicable to any unit. For instance, the unit given here is in mL. Since the ratio is in $\text{2}$ parts acid to $1$ part water, which is also equivalent to $\text{2 mL}$ acid to $\text{1 mL}$ water.

Hence, you have to add $\text{2 mL}$ of acid to water and not vice versa. Other acids are highly reactive to water. Also, add the acid slowly to avoid violent reactions.

Conclusion

Add 2 mL of acid to water.