Question

In an ion with an unknown charge, the total mass of all the electrons was determined to be 2.19 ✕ 10−26 g, while the total mass of its protons was 4.34 ✕ 10−23 g. What is the identity and charge of this ion? (Enter your answer in the form X^q±.)

Answer 1

Answer:

$\large \boxed{\text{Fe ^{{2+}} }}$

Explanation:

1. Number of electrons

$\text{Number of electrons} = 2.19 \times 10^{-26}\text{ g} \times \dfrac{\text{1 electron}}{9.109 \times 10^{-28}\text{ g}} = \text{24 electrons}$

2. Number of protons

$\text{Number of protons} = 4.34 \times 10^{-23}\text{ g} \times \dfrac{\text{1 proton}}{1.673 \times 10^{-24}\text{ g}} = \text{26 protons}$

3. Identify the ion

An atom with 26 protons is iron, Fe.

A neutral atom of iron would have 26 electrons.

The ion has only 24 electrons, so it has lost two. The ion must have a charge of +2.

$\text{The symbol for the ion is \large \boxed{\textbf{Fe ^{\mathbf{2+}} }} }$