Choose the correct statement:

A. Diamond is the hardest and graphite is the softest

B. Graphite is the hardest and diamond is the softest

C. Both diamond and graphite have equal hardness

D. Diamond is soft and graphite is hard

Everyday Science · Atoms, Elements & Compounds · page 13 of 15

Some Important Elements MCQs with Answers

Includes 16 past paper MCQs (marked).

Timed quizzes, instant results, track your progress — free

Practice these MCQs in the app

All Everyday Science chapters

Some Important Elements MCQs (121–130)

10 MCQs with answers and a short one-liner. Hide answers to test yourself.

Past paper MCQs in this chapter · See all past papers

Answers and one-liners are hidden. Tap an option to check that question, or show all.

121.
Which of the following best describes silicon in terms of its electrical properties?
Correct Answer: C. Semi-conductor
One-liner
Silicon is best described as a semi-conductor because its electrical conductivity lies between that of a conductor and an insulator.
122.
Electronegativity of Al is approximately equal to that of
Correct Answer: A. Be
One-liner
The electronegativity of aluminium (Al) is approximately equal to that of beryllium (Be).
123.
Which isotope is used to study the uptake of phosphorus containing fertilizers?
Correct Answer: D. Phosphorus - 32
One-liner
Phosphorus-32 is the radioactive isotope used to study the uptake of phosphorus-containing fertilizers in plants.
124.
Past Paper MCQ
Which form of phosphorus is used in safety matches?
Correct Answer: B. Red
One-liner
Red phosphorus is used in safety matches.
125.
Which noble gas is present on the earth due to radioactivity decay?
Correct Answer: D. Radon
One-liner
The noble gas present on Earth due to radioactive decay is Radon.
126.
Which element is found in organisms as 49% of their dry body weight?
Correct Answer: C. Carbon
One-liner
Carbon constitutes about 49% of the dry body weight of living organisms.
127.
What is the chemical symbol for "silver"?
Correct Answer: B. Ag
One-liner
The chemical symbol for silver is Ag, derived from its Latin name *argentum*.
128.
Which element belongs to group IVA of the periodic table?
Correct Answer: D. Lead
One-liner
Lead (Pb) belongs to Group IVA (Group 14) of the periodic table.
129.
The valency of Noble gases in general is _?
Correct Answer: C. Zero
One-liner
The valency of Noble gases in general is zero because their outermost electron shell is completely filled, making them chemically inert.
130.
Choose the correct statement:
Correct Answer: A. Diamond is the hardest and graphite is the softest
One-liner
Diamond is the hardest and graphite is the softest — both are allotropes of carbon with vastly different physical properties due to their atomic arrangements.

Previous chapter: Non-metal Elements Next chapter: Compounds

Some Important Elements MCQs with Answers

Some Important Elements MCQs (121–130)

Subjects

Exams

Platform

Legal