Question

4. Rewrite the following statements in a correct form after correction, if necessary.
(a) Periods are horizontal rows of elements.
(b) Groups have elements with consecutive atomic numbers.
(c) Elements in the same period have equal valency.
(d) Isotopes are the elements of the same group.​

Answer 1

(a) is correct. Periods are horizontal rows and groups are vertical columns

(b) is false. Consecutive atomic no. Is in periods.

(c) is false. Bcoz elements In same period have different valency and element in same group have same valency

(d). Isotopes have same no. Of proton and electron but different neutron

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