Metals and Non-Metals — Science STD 10 — Question

State whether the following statements are true or false:
According to Mendeleev’s periodic law, the properties of elements are a periodic function of their atomic numbers.

Carbon and its compounds are used as fuels because they burn in air releasing a lot of heat energy. [True/ False]

State whether the following statement is true or false:
Only 10 per cent of the light energy given by the sun is available for transfer at each higher trophic level in a food chain.

Magnification produced for an object at 2F by a convex lens is m = +1. [True/ False]

State whether the following statements are true or false,
A wire with a green insulation is usually the live wire of an electric supply.

State whether the following statement is true or false:
The axis of earth’s imaginary magnet and the geographical axis coincide with each other.

Photosynthesis fix up the solar energy and make it available in a food chain.

Secondary consumers and tertiary consumers, both are carnivores.

State whether the following statement is true or false:
The aqueous solution of an ionic compound conducts electricity because there are plenty of free electrons in the solution.