Question

When a metal N reacts with a non-metal X, it forms a compound of NX2 type.

(a) Identify the group in which element N and X are placed in modern periodic table.
(b) Write the number of valence electrons present in element N and element X.
(c) Write an example of NX2 type of compound.

Answer 1

Element N is in Group 2 with two valence electrons, and X is in Group 17 with seven valence electrons. An example of an NX2 compound is calcium chloride (CaCl2).

Step-by-step explanation:

When a metal N reacts with a non-metal X, and forms a compound of type NX2, we can deduce the following:

• (a) The metal N must be in Group 2 (or IIA) of the modern periodic table because it forms a compound where the metal has a 2+ charge to balance the two X ions with a − charge each. The non-metal X is in Group 17 (or VIIA) as it forms a diatomic molecule with a 1− charge each to make NX2.
• (b) Element N from Group 2 has two valence electrons, and element X from Group 17 has seven valence electrons.
• (c) An example of an NX2 type compound is calcium chloride (CaCl2), where calcium (Ca) is from Group 2 and chlorine (Cl) is from Group 17.