vhp 10 question below

Question

What is the pHpH of a solution prepared by dissolving 3.40 gg Ca(OH)2Ca(OH)2 in water to make 815 mLmL of solution?

Express your answer using two decimal places.



Sodium oxide, Na2ONa2O, reacts with water to give NaOHNaOH.

1. Write a balanced equation for the reaction.

Express your answer as a chemical equati

2. How many milliliters of 0.0100 MM HClHCl are needed to neutralize the NaOHNaOH solution prepared in the part B?

Express your answer using three significant figures.

Answer 1

Hi Asma,

I am going to focus on the chemical equation (see my comments above regarding the rest).

Sodium oxide reacts with water to give sodium hydroxide. First let us translate this sentence to the language of chemical reaction equations:

Sodium oxide Na₂O

reacts with +

water H₂O

to give →

sodium hydroxide NaOH

or

Na₂O + H₂O → NaOH

The above reaction equation is not (yet) balanced, so our next task is to balance it.

We will start with Na. There are two Na on the left side of the equation, but only one on the right side. To balance, we need to put 2 before NaOH on the right side as follows.

Na₂O + H₂O → 2 NaOH

Next, let’s look at O. There are two oxygens on the left and now there two oxygens on the right. No further action required.

Finally, let’s look at H. There are two hydrogens on the left and now there are two hydrogens on the right. It means that the equation is balanced.

Na₂O + H₂O → 2 NaOH