Question

1. which of the following groups contains members with similar chemical reactivity?

a k, ca, sc
b v, cr, mn
c cu, ag, au
d n, o, f

1. which of the following groups does not contains members with similar chemical reactivity?

a ni, pd, pt
b c, n, o
c li, na, k
d f, cl, br

Explanation:

Step1: Analyze Q9 group properties

Elements in the same group (vertical column of periodic table) have the same number of valence electrons, so they have similar chemical reactivity.

• A: K, Ca, Sc are in Period 4, Groups 1,2,3 (different groups)
• B: V, Cr, Mn are in Period 4, Groups 5,6,7 (different groups)
• C: Cu, Ag, Au are in Group 11 (same group, coinage metals)
• D: N, O, F are in Period 2, Groups 15,16,17 (different groups)

Step2: Analyze Q10 group properties

Elements not in the same group will have different valence electrons, so different reactivity.

• A: Ni, Pd, Pt are in Group 10 (same group)
• B: C, N, O are in Period 2, Groups 14,15,16 (different groups)
• C: Li, Na, K are in Group 1 (same group, alkali metals)
• D: F, Cl, Br are in Group 17 (same group, halogens)

Answer:

1. C. Cu, Ag, Au
2. B. C, N, O