P-1 Periodic Classification of Element — Science STD 10 — Question

What percentage of the solar energy is trapped and utilised by the plants?

Which different products can be produced with the help of Microbes?

What is the name of tiny air - sacs at the end of smallest bronchioles in the lungs?

Which phenomenon makes us see the sun:

1. A few minutes before actual sunrise?
2. A few minutes after actual sunset?

Which of the following type of energy is used by living organisms to perform vital life processes?
Kinetic energy, Chemical energy, Potential energy, Nuclear energy.

Does a new substance form when a solute dissolves in a solvent?

With which substance should chlorine be treated to get bleaching powder?

Sodium, Aluminium, Chlorine, Carbon.

Name the part of the retina which is insensitive to light.

Explain why, the surface of some metals acquires a dull appearance when exposed to air for a long time.