Question

select the correct answer.
what is the chemical formula for the compound magnesium perchlorate? use the list of polyatomic ions and the periodic table to help you answer.
a. mgclo
b. mgclo4
c. mg2clo4
d. mg(clo4)2

Explanation:

Step1: Determine the charge of magnesium ion

Magnesium (\(Mg\)) is in group 2 of the periodic table. So, the magnesium ion has a charge of \(Mg^{2+}\).

Step2: Determine the charge of perchlorate ion

From the table, the perchlorate ion is \(ClO_{4}^{-}\).

Step3: Use the criss - cross method to form the formula

For an ionic compound, the sum of the charges of cations and anions must be zero. Let \(x\) be the number of \(Mg^{2+}\) ions and \(y\) be the number of \(ClO_{4}^{-}\) ions. We have \(2x+( - 1)y = 0\). When \(x = 1\), then \(y = 2\).

Answer:

B. \(Mg(ClO_{4})_{2}\)