Question

Write the balanced equation for the following chemical reactions: Sodium + Water → Sodium hydroxide + Hydrogen

Answer 1

Balanced chemical equation: A balanced chemical equation is the representation of a chemical reaction in which the number of atoms of each element is the same on both the reactant and product sides.

Word equation to symbolic equation:

• In the given reaction, Sodium reacts with water vigorously to form Sodium hydroxide and Hydrogen.
• The chemical reaction can be represented as:

$\underset{\mathrm{Sodium}}{\mathrm{Na}\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Sodium}\mathrm{hydroxide}}{\mathrm{NaOH}\left(\mathrm{aq}\right)}+\underset{\mathrm{Hydrogen}}{{\mathrm{H}}_2\left(\mathrm{g}\right)}$

Balancing the Chemical Equation:

Step 1: Write the number of atoms of each element

$\underset{\mathrm{Sodium}}{\mathrm{Na}\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Sodium}\mathrm{hydroxide}}{\mathrm{NaOH}\left(\mathrm{aq}\right)}+\underset{\mathrm{Hydrogen}}{{\mathrm{H}}_2\left(\mathrm{g}\right)}$

Element	Reactant side	Product Side
$\mathrm{Na}$	$1$	$1$
$\mathrm{O}$	$1$	$1$
$\mathrm{H}$	$2$	$3$

• From the table, it is clear that the atoms of Hydrogen are not balanced.

Step 2: Balancing the unbalanced atoms

• In order to balance the equation, we will make the coefficient of $\mathrm{Na},{\mathrm{H}}_2\mathrm{O},\mathrm{NaOH}$ as $2$
• Now the equation becomes

$\underset{\mathrm{Sodium}}{2\mathrm{Na}\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Sodium}\mathrm{hydroxide}}{2\mathrm{NaOH}\left(\mathrm{aq}\right)}+\underset{\mathrm{Hydrogen}}{{\mathrm{H}}_2\left(\mathrm{g}\right)}$

Element	Reactant side	Product Side
$\mathrm{Na}$	$2$	$2$
$\mathrm{O}$	$2$	$2$
$\mathrm{H}$	$4$	$4$

Hence, the balanced chemical equation is $\underset{\mathrm{Sodium}}{2\mathrm{Na}\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Sodium}\mathrm{hydroxide}}{2\mathrm{NaOH}\left(\mathrm{aq}\right)}+\underset{\mathrm{Hydrogen}}{{\mathrm{H}}_2\left(\mathrm{g}\right)}$