Question

1. 1 Water makes up between 70-90% of the weight of most life forms, and nearly all chemicals present in living matter are soluble in it. Water is such a good solvent because the molecular structure of a water molecule is polar, having a negative charge at one end and a positive charge at the other end. Which model best represents a water molecule? A. B. C. D.

Answer 1

Answer:

The correct model is D.

Note: The first attachment below shows the different models. The second attachment shows the correct structural model of the water molecule.

Explanation:

A water molecule is composed of one atom of oxygen and two atoms of hydrogen.

A water molecule is polar, i.e. it contains positively and negatively opposite ends. The polar nature of the water molecule is due to strong electronegativity of oxygen which results in an uneven sharing of the bonding electrons between oxygen and hydrogen. The oxygen atom attracts the shared electrons more to itself, thereby, it acquires a partial negative charge, while the hydrogen atoms acquire a partial positive charge.

The bond angle between the oxygen and hydrogen atoms is approximately 105°. Therefore, from the first attachment below, the correct model for the water molecule is D.