Write the formulas for the following ionic compounds: (a) copper bromide (containing the Cu1 ion), (b) man- ganese oxide (containing the Mn31 ion), (c) mercury iodide (containing the Hg21 ion), and (d) magnesium phosphate (containing the PO342 ion).

CuBr

Mn2O3

Hg2I2

Mg3(PO3)2

Explanation:

When writing the formula of an ionic compound, we use the exchange method.

The symbol of each element or ion is written with it's charge as a superscript. The charges are then interchanged, the signs are dropped and the figures are written as subscripts. This gives the formula of compound.

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms