Explanation

Discontinuous variation involves traits like blood group or tongue rolling, where individuals fall into clear, separate categories.

There are no intermediate states—either you have the trait or you don’t.

Explanation

Reforming is the process used to separate hydrogen from hydrocarbons (like methane or naphtha) by applying heat in the presence of a catalyst.

This is typically called steam methane reforming (SMR).

Explanation

Normal salts are formed when all replaceable hydrogen atoms in an acid are replaced by metal ions.

They do not contain any replaceable hydrogen or hydroxyl groups.

Explanation

Explanation

Conductivity is a physical property that describes how well a material allows heat or electricity to pass through.

Reactivity and toxicity are chemical properties, as they involve changes in the substance's composition.

Explanation

A dilute solution contains a relatively small amount of solute compared to the solvent.

This means the solute is less concentrated in the solution.

Explanation

Galaxies are the basic building blocks of the universe, consisting of stars, gas, dust, and dark matter.

The universe contains billions of galaxies, each with millions or billions of stars.

Explanation

Tungsten is commonly used as the target material in X-ray tubes due to its high atomic number and ability to withstand the high heat generated during X-ray production.

Its properties make it efficient in producing X-rays.

Explanation

White blood cells are called leucocytes, not red blood cells.

Red blood cells are called erythrocytes.

Explanation

An aquifer is a layer of rock or sediment that stores and transmits groundwater.

Porifera relates to animals (sponges).