Explanation

Tertiary consumers are at the top of the food chain and feed on secondary consumers.

Lion, tiger, and hawk are carnivores that eat other carnivores or herbivores.

Explanation

Cyclic ethers containing two ether groups are called crown ethers.

These compounds have a ring structure with multiple oxygen atoms, forming a "crown-like" shape that can bind to metal ions. 

Explanation

The kinetic molecular theory states that gases are made up of small particles called molecules.

These molecules are in constant random motion and collide with each other and the container walls.

Explanation

A compound is a pure substance formed when two or more different elements chemically combine in a fixed ratio.

Examples include water (H₂O) and carbon dioxide (CO₂).

Explanation

Polychromatic light contains multiple wavelengths or colors of radiation.

It is the opposite of monochromatic light, which has only a single wavelength.

Explanation

An alkali is a base that dissolves in water to give hydroxide (OH⁻) ions.

Common examples include sodium hydroxide (NaOH) and potassium hydroxide (KOH).

Explanation

Monosaccharides are the simplest form of carbohydrates.

They are called simple sugars because they cannot be broken down into smaller sugar units.

Explanation

Vitamin D helps the body absorb calcium from the intestines.

It regulates blood calcium levels by enhancing calcium absorption and reducing calcium loss from bones.

Explanation

Diffusion is the process where particles move from an area of high concentration to low concentration.

Ink spreads evenly in water due to molecular motion, resulting in uniform distribution.

Explanation

A reducing agent, also known as a reductant.

It is a substance that causes another substance to be reduced by donating electrons to it.

In the process, the reducing agent itself becomes oxidized, as it loses electrons.

This means that the reducing agent's oxidation state increases.