Tag: physical properties of metals and non-metals

Questions Related to physical properties of metals and non-metals

Iodine is a non-metal which has metallic lusture.

  1. True

  2. False


Correct Option: A
Explanation:

Its because going down the group the size of the atom increases because of shielding effect due to which the interaction between the atom and the outermost electron decreases so these electrons on the surface of iodine become excited by absorbing heat energy from light so when they release this energy and come to their normal state, they emit this light so it appears that they have lustrous surface.

A non-metal which is a good conductor of electricity is:

  1. graphite

  2. hydrogen

  3. sodium

  4. mercury


Correct Option: A
Explanation:

1) Graphite is soft and slippery because there are only weak intermolecular forces between its layers. Graphite is a good conductor of heat and electricity.

2) Graphite can conduct electricity because of the delocalised (free) electrons in its structure.

3) These arise because each carbon atom is only bonded to 3 other carbon atomsHowever, in diamond, all 4 outer electrons on each carbon atom are used in covalent bonding, so there are no delocalised electrons.

4) These electrons in graphite are free to move through the structure.

Chlorine is greenish yellow gas.

  1. True

  2. False


Correct Option: A
Explanation:

It is a pale green gas and is used in cleaning products. Chlorine is an greenish-yellow gaseous element. Its atomic number is 17, and is one of the class called halogens in the periodic table. Large concentration of chlorine are dangerous.

Graphite is the only non-metal which is good conductor of electricity.

  1. True

  2. False


Correct Option: A
Explanation:
Graphite is composed of carbon atoms which are situated in layers. Because of that electron are free to move and conduct the electricity. Although it is a non-metal, good conductor of electricity. 

Non-metals are present in which state?

  1. Solid

  2. Liquid

  3. Gaseous

  4. All of the above


Correct Option: D
Explanation:

Answer: all of the above 

Most of metal exist in two out of three states of matter at room temperature
Eg: gases- oxygen,  solid-carbon

Only bromine exist in liquid state at room temperature.

Which of the following is/ are property of non-metals?
(a) Non-metals are malleable.
(b) Non-metals are non ductile.
(c) Non-metals are brittle.

  1. a, b

  2. b, c

  3. a, c

  4. a, b, c


Correct Option: B
Explanation:

Non-metals are non-malleable, non-ductile when they are beaten with hammer or stretched they break into pieces, so they are brittle.

Which of the following when stretched, break into pieces?

  1. Calcium

  2. Phosphorus

  3. Iron

  4. Radium


Correct Option: B
Explanation:

When sulphur or phosphorus is stretched, they break into pieces. Non metals are non-malleable non-ductile.

Which one is the softest solid non-metal among the following?
Diamond, Oxygen, Sulphur, Bromine

  1. Diamond

  2. Oxygen

  3. Sulphur

  4. Bromine


Correct Option: C
Explanation:

Most of the solid non-metals are quite soft. For example - sulphur and phosphorous are solid non-metals which are quite soft.

 Which of the following non-metal is lustrous?

  1. Diamond

  2. Iodine

  3. Both $A$ and $B$

  4. None of the above


Correct Option: C
Explanation:

Diamond and iodine both are non metal and lustrous.

Which of the following is the largest in size?

  1. $Br$

  2. $I$

  3. $I^-$

  4. $I^+$


Correct Option: C
Explanation:

Answer : $I^{\ominus}$

(1) We know that from top to bottom atomic size is increases. So $I$ its having higher atomic size then $Br$.
(2) In $I, I^{\ominus}$ and $I^{\oplus}$
$I^{\ominus}$ have the largest atomic size because $I^{\ominus}$ has one extra electron in its valence shell which lead to increase in atomic size.
$\therefore I^{\ominus} > I > I^{\oplus} > Br$.