Metals and Non-Metals — Science STD 10 — Question

Complete the following sentence:
Domestic gas cylinders like Indane contain mainly _______.

What is the name of in-built ‘arrangement’ in our body which controls the timing and amount of hormones released by various endocrine glands in the body?

Is it possible to have an element having atomic number 1.5 placed between hydrogen and helium?

What is the difference between two consecutive homologues:

1. In terms of molecular mass?
2. In terms of number and kind of atoms per molecule?

What change should be made in an a.c. generator so that it may become a d.c. generator?

What gaseous waste products are excreted by plants?

What are the criteria you would consider when trying to categorise something as a good fuel?

Which of the two has a branched chain: isobutane or normal butane?

Explain why chlorine is used for sterilising drinking water supply.

Name the material which is used for making the filaments of an electric bulb.