Language of Chemistry — CHEMISTRY STD 9 — Question

What do you understand by the following terms?
saturated solution

The atom of an element is made up of 4 protons, 5 neutrons and 4 electrons. What are its atomic number and mass number?

What do you understand by the following terms?
Basic radical

Name and state the following with reference to the elements of the first three periods of the periodic table.
Noble gas having electronic configuration : 2, 8, 8.

Which property of water enables it to modify the climate?

This question refers to elements of the periodic table with atomic numbers from 3 to 18. In the table below, some elements are shown by letters, even though the letters are not the usual symbols of the elements.

3	4	5	6	7	8	9	10
A	B	C	D	E	F	G	H
11	12	13	14	15	16	17	18
I	J	K	L	M	N	O	P

What is the electronic configuration of G?

Give reason:
Inert gases do not form compounds.

Identify the gases from the observations:
A colourless gas having a pungent and irritating smell, which turns blue litmus red. It gives dense white fumes when a glass rod dipped in ammonium hydroxide solution is held in it.

Atomic numbers of elements P, Q, R and S are 1, 2, 7 and 11 respectively. Classify them as metals, non-metals and noble gases.