[ Question Bank ] - 2022 — Science STD 10 — Question

The elements lithium and beryllium are in the same period because their valencies are similar.

• Right

• Wrong

When red light falls on the eyes, the cells responding to red light get excited more than those responding to other colours and we get the sensation of red colour.

Lanthanides and actinides are also called the d-block elements.

Mendeleev was the first who successfully classified all known elements.

Metals are known as sonar metals.

Two carbon atoms can always form one or two covalent bonds.

In CGS system, heat is measured in calorie.

Resistivity of a conductor does not depend upon its temperature.

If the distance between two masses is doubled, the gravitational force between them becomes less than the previous force.

Atomic energy is a very good energy source.