Which of the following is the correct chemical formula for the ionic compound formed between lithium (Li) and bromine (Br)?

• A. Li2Br
• B. LiBr2
• C. Li2Br2
• D. LiBr

Answer: (D)

Verified step by step guidance

1. Identify the charges of the ions formed by lithium and bromine. Lithium (Li) is an alkali metal and typically forms a +1 cation, written as Li\^{+}. Bromine (Br) is a halogen and typically forms a -1 anion, written as Br\^{-}.
2. Determine the ratio of ions needed to balance the overall charge of the compound. Since lithium has a +1 charge and bromine has a -1 charge, one Li\^{+} ion will balance one Br\^{-} ion.
3. Write the chemical formula by combining the ions in the ratio that results in a neutral compound. Because the charges are equal and opposite, the formula is simply LiBr, with one lithium ion and one bromide ion.
4. Check the other options to see if they maintain charge neutrality. Li2Br would imply two Li\^{+} ions (+2 total) and one Br\^{-} ion (-1 total), which is not neutral. LiBr2 would imply one Li\^{+} ion (+1) and two Br\^{-} ions (-2), also not neutral. Li2Br2 simplifies to LiBr, but is not the conventional way to write the formula.
5. Conclude that the correct chemical formula for the ionic compound formed between lithium and bromine is LiBr, reflecting a 1:1 ratio of Li\^{+} and Br\^{-} ions to maintain electrical neutrality.