I think the correct answers from the choices listed above are the first, third and the last option. Ionic compounds are compounds that dissociates into ions when in aqueous solution. From the list, NH4Cl, KF and MgO are the ionic compounds. Hope this answers the question.
The answer to this problem is Beryllium is an alkaline earth metal.
Answer:
148 grams of relative atomic mass
Explanation:
magnesium atomic mass : 24
nitrogen : 14
oxygen : 16
24 × 1
14 × 1 × 2
16 × 3 × 2
24 + 28 + 80 = 148 grams