Question

How many hydrogen atoms are in five molecules of ${H_2}O$?

Answer 1

The water is a chemical compound which is used as the universal solvent as it dissolves maximum number of chemical compounds in it. The molecular formula of water is ${H_2}O$. A single water molecule contains two hydrogen atoms and one oxygen atom.

Complete step by step answer:
Water is a universal solvent which can dissolve most of the chemical elements and chemical compounds. Water is the basic need of all the living beings. The water is formed by the reaction of hydrogen and oxygen.
The reaction for the formation of water is shown below.
$2{H_2} + {O_2} \to 2{H_2}O$
In this reaction, two mole of hydrogen react with one mole of oxygen to form two mole of water.
The molecular formula of water is ${H_2}O$. It contains two hydrogen atoms and one oxygen atom. As, in the question 5 molecules of water ${H_2}O$ is given. As, one molecule of water contains 2 hydrogen atoms, therefore 5 molecules of water ${H_2}O$ contains $\Rightarrow 5 \times 2 = 10$ hydrogen atoms.
In the water molecule, the central atom oxygen is bonded with two hydrogen atoms by a polar covalent bond by the mutual sharing of electrons. The oxygen atom has partial negative charge and hydrogen has partial positive charge. The hydrogen atom of one water molecule is bonded by the oxygen of another water molecule by a hydrogen bond due to electronegativity difference between the hydrogen atom and oxygen atom.
Therefore, 10 hydrogen atoms are present in 5 molecules of water ${H_2}O$.

Note:
In water molecules, the arrangement of the atoms in the molecule is in tetrahedral form. As the repulsion from the lone pair combination is more than bond pair repulsion, the geometry becomes distorted tetrahedron (bent shape). The angle is 104.5 degrees.