Periodic classification of elements Worksheet-6

Periodic classification of elements Worksheet-6

As we go from left to right in period two of the periodic table, gram atomic volume of the elements ____.

A. Will change indefinitely

B. Increases at a constant rate

C. First increases then decrease

D. First decreases and then increases

In the main group elements (i) as we proceed down the same group in the periodic table and (ii) as we proceed from left to right in the same period, the atomic radius

A. (i) Increase continuously; (ii) Decreases continuously

B. (i) Decreases continuously; (ii) Increases continuously

C. (i) Increases continuously; (ii) Decreases up to the group IV and then increases upto the end of the period.

D. (i) Decreases continuously; (ii) Decreases upto the group IV and then increases upto the end of the period.

Group comprising of all metals is _____.

A. IIIA B. VA C. VIIA D. IIA

The atomic number of an element is derived from ____.

A. Number of electrons B. Number of protons

C. Number of neutrons D. Number of isotopes

E. Number of nucleons

Which of the following properties remain unchanged on descending a group in the periodic table?

A. Atomic size B. Density

C. Valence electrons D. Metallic character

Which of the following element does not occur in liquid form?

A. Hg B. Li C. Ga D. Br

Which of the following has the maximum atomic radius?

A. Al B. Si C. P D. Mg

On going down a main sub-group in the periodic table (example Li to Cs in IA or Be to Ra in IIA), the expected trend of changes in atomic radius is a

A. Continuous increase

B. Continuous decrease

C. Periodic one, an increase followed by a decrease

D. A decrease followed by increase

An element of atomic weight 40 has 2, 8, 8, 2 as the electronic configuration. Which one of the following statements regarding this element is not correct?

A. It belongs to II group of the periodic table

B. It has 20 neutrons

C. The formula of its oxide is MO₂

D. It belongs to 4th period of the periodic table

In the periodic table, the metallic character of elements _____.

A. Decreases from left to right across a period and on descending a group

B. Decreases from left to right across a period and increases on descending a group

C. Increases from left to right across a period and on descending a group

D. Increases from left to right across a period and decreases on descending a group

The correct order of reactivity of halogen is _____.

A. Flourine > bromine > chlorine > iodine

B. Flourine > chlorine > bromine > iodine

C. Iodine > bromine > chlorine > fluorine

D. Bromine > chlorine > flourine > iodine

Fluorine, chlorine, bromine and iodine are placed in the same group (17) of the periodic table, because _____.

A. They are non-metals

B. They are electronegative

C. Their atoms are generally univalent

D. They have 7 electrons in the outermost shell of their atom

The valence shell of calcium contains _____.

A. 8 electrons B. 6 electrons C. 4 electrons D. 2 electrons

Which of the following gas does not have an octet or eight electrons in the outer shell?

A. Ne B. Ar C. Rn D. He

Answer Key:

Explanation: First decreases to a minimum and then increases

Explanation: Atomic radius decreases from left to right in a

period and increases from top to bottom in a group.

Explanation: In IIA group all elements are metals while in IIIA, IVA and VIIA groups non-metallic elements are also present. Group II A elements are called alkaline earth metals.

Explanation: The atomic no. of an element is derived from the number of proton because during chemical reaction number of electrons undergo change.

Explanation: Valency of the elements in a group is same as the electronic configuration is same.

Explanation: Mg, as we move across the period atomic radius decreases.

Explanation: Continuous increase as no. of shells increases down the group.

Explanation: Its valency is 2. So it will form MO. (valency of oxygen is also 2)

Explanation: Fluorine is more reactive than chlorine, bromine and iodine.

Explanation: Electronic configuration of outermost shell of group-17 or halogens are ns²np⁵.

Explanation: Valence shell configuration for IIA group elements is : ns²

Explanation: He has the atomic number 2 so it does not have octet.