Question

What mass of hydrogen is produced when 0.400 mol of water react completely in the following equation?2 Na + 2 H20 --> 2 NaOH + H2a. 0.404 gb.0.323 gc. 2.02 gd. 1.62 g

Answer 1

Answer:

Option A is correct. 0.404g

Explanation:

Given the chemical reaction between sodium and water as shown below:

$2Na+2H_2O\rightarrow2\text{NaOH}+H_2$

From the reaction, we can see that 2 moles of water molecules react to form 1 mole of the Hydrogen molecule. This shows that 0.400moles of water will react with sodium to form 0.200 moles of H2

Get the mass of hydrogen produced using the formula:

$\text{Mass}=nu\text{mber of moles }\times molar\text{ mass}$

Since the molar mass of hydrogen is 2.016 g. The mass of hydrogen produced will be expressed as;

$\begin{gathered} \text{Mass of H}_2=0.200\times2.016 \\ \text{Mass of H}_2=0.4032g \end{gathered}$

This shows that the mass of the hydrogen produced when 0.400 mol of water reacts completely is approximately 0.404g