Question

Elements are arranged in Modern Periodic table in increasing order of their

atomic numbers. Metals are on left hand side and middle of periodic table

mainly and non-metals are on right hand side. A zig-zag diagonal line divides

metals and non-metals. Elements near zig zag line are called

metalloids.Elements of same group have same number of valence

electron.,but different number of shells.Elements of same period have

different number of valence electrons,but same number of shells.Elements in

the middle of the periodic table are called transition metals.

(a)Which one of the following statements are correct.

i) All group contain both metal and nonmetals.
ii) In group 17, reactivity decreases down the group

(iii) In group 1, reactivity decreases down the group.

(iv) Atoms of same group have same number of electrons

b) Which of the following is correct formula of hydrides of phosphorus?

i)PH2 (ii) PH3 (iii) PH5 (iv) PH4

(c) out of Na and K which element is more electropositive ​

Answer 1

Answer:

a.ii) In group 17, reactivity decreases down the group

b.ii)PH3

c.K is the more electropositive