Which of the following element combinations will form ionic compounds? 1. Ca {Z = 20) and Ti (Z = 22) 2. Si (Z = 14) and Br [Z = 35) 3. Mg [Z = 12) and Cl {Z = 17) Select the correct answer using the code given below.

Ionic compounds typically form through the transfer of electrons between a metal and a non-metal to achieve a stable noble gas configuration [4]. In combination 1, Calcium (Z=20) and Titanium (Z=22) are both metals; Calcium is an alkaline earth metal, and Titanium is a transition metal, so they do not form ionic compounds with each other. In combination 2, Silicon (Z=14) is a metalloid and Bromine (Z=35) is a non-metal; Silicon typically forms covalent bonds rather than ionic ones due to the energy required to lose or gain four electrons [3]. In combination 3, Magnesium (Z=12) is a metal that loses two electrons to form a Mg2+ cation, while Chlorine (Z=17) is a non-metal that gains one electron to form a Cl- anion [1]. This electron transfer results in the formation of the ionic compound Magnesium Chloride (MgCl2) [4].

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 3: Metals and Non-metals > QUESTIONS > p. 49
2. [3] Science , class X (NCERT 2025 ed.) > Chapter 3: Metals and Non-metals > 3.3 HOW DO METALS AND NON-METALS REA ALS REACT? > p. 46
3. [4] Science , class X (NCERT 2025 ed.) > Chapter 3: Metals and Non-metals > 3.3 HOW DO METALS AND NON-METALS REA ALS REACT? > p. 47