(a) Choose the correct answer from the option: - Noon Academy

(a) Choose the correct answer from the option:

Chemistry | Class 10 | ICSE | Periodic Table, Periodic Properties and Variations of Properties | Selina

(a) Choose the correct answer from the option:

An element in Period 3 whose electronic affinity is zero.

A. Neon B. Sulphur

C. Sodium D. Argon

(b) Give reason:

(i) The ionisation potential of the element increases across a period.

(ii) Alkali metals are good reducing agents.

(c) There are three elements E, F, G with atomic numbers 19, 8 and 17 respectively.

Classify the above elements as metals and non-metals.

(d) Name a metal present in Period 3, Group I of the periodic table.

Answers:

(a) Correct Answer is option D; Explanation: Argon is the element in Period 3 whose electronic affinity is zero.

(b)

(i) Across a period, the attraction between the nucleus and the electron increases as the atomic radius decreases.

(ii) Alkali metals have a good tendency to lose electrons.

(c)

E – Metal

F – Non-metal

G – Non-metal

(d) Sodium (Na) is the metal present in Period 3, Group I of the periodic table.

i

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