2022_7.2 Group Properties MCQs

Q11:

• A

• B

• C

• D

Answer explanation

Remember:

The group number is equal to the number of valence electrons.

Q13:

• A

• B

• C

• D

Answer explanation

Remember:

The colour of halogens becomes darker down the group.

The melting/boiling points of the halogens increases down the group.

Q14:

• A

• B

• C

• D

Answer explanation

Remember:

The colour of halogens becomes darker down the group.

The melting/boiling points of the halogens increases down the group.

Q15:

• A

• B

• C

• D

Answer explanation

Remember:

Caesium is an alkali metal.

All alkali metals react with water to form metal hydroxide and hydrogen gas.

A: It CONDUCTS electricity.

B: It forms a BASIC oxide

C: It forms an ionic chloride CsCl

Q16:

• A

• B

• C

• D

Answer explanation

Remember:

Argon gas's atomic(proton) no. is 18 and its electronic configuration is 2, 8, 8

Q17:

• A

• B

• C

• D

Answer explanation

Remember:

The trend of melting/boiling points of alkali metals (Group I) DECREASES DOWN THE GROUP

B: Their reactivities INCREASES on descending the group

C: They form IONIC bonds with the halogens (cause Metal-Non Metal)

D: They form HYDROXIDES on reacting with water

Q20:

• A

• B

• C

• D

Answer explanation

Remember:

A: Noble gases are MONATOMIC ATOMS.

Q20:

• A

• B

• C

• D

Q23:

• A

• B

• C

• D

Answer explanation

Remember:

Monatomic gas = noble gas = unreactive/inert

Q24:

Hint: '-' = loss of electron and '+' = gain of electron

• A

• B

• C

• D

Answer explanation

Remember:

Alkali Metals (Group I) LOSES 1 electron to form a positively charge metal ion.

Thus,

X - e^- --> X^+