Nature of Matter: Elements, Compounds, and Mixtures — Science STD 8 — Question

The underlined words in the following sentence have been jumbled up. Write them in their correct form. Loca is obtained from mines.

In toy telephone the sound travels through which medium?

A gas is utilised by the trees and plants in photosynthesis. The same gas also traps the heat rays reflected by the Earth and is also given out by humans during respiration. Name the gas and the phenomenon of increase in temperature for which it is responsible.

Give a suitable word for each of the following statements. It marks the beginning of reproductive period.

Which force do the animals apply while moving, chewing and doing other activities?

What happens to the needle of a compass kept nearby when electric current is switched on in a wire? Why does this happen?

Which of the following cannot transmit sound? Water, Vacuum, Aluminium, Oxygen gas.

Find out the wrong statements and write them in their correct form. Water which is suitable for drinking is called soft water.

State whether the following statements are True or False: External fertilization takes place in frog.

Identify the following micro-organisms :
I live in every kind of environment, and inside your gut.