Question

In the formula X2O5, the symbol X could represent an element in Group

(1) 1 (3) 15
(2) 2 (4) 18

Answer 1

In the compound X2O5, X represents an element that could potentially be from Group 15, as elements from this group are known to form oxyanions with five oxygen atoms.

Step-by-step explanation:

In the formula X2O5, the symbol X likely represents an element that forms an oxyanion with five oxygen atoms. Based on typical oxyanion formation and the periodic table, elements in Group 15 are known to form such compounds. For example, nitrogen (N) in Group 15 forms N2O5, which has a similar formula structure to the given compound X2O5. Therefore, X could represent an element in Group 15.

Answer 2

Answer: (3) 15

Explanation: We criss-cross down the oxidation numbers to get the subscripts for the correct formulas. That means the X has an oxidation number of 5. The element with the + oxidation number is always written first so it is +5. Of the groups names, only group 15 has +5 as an oxidation number.