Chemistry

Problem

Which of the following pairs of cations can be separated by adding

\text{NH}_4\text{Cl}, \text{NH}_4\text{OH}

and then

(\text{NH}_4)_2\text{CO}_3

to the mixture? a.

\text{Ca}^{2+}, \text{Mg}^{2+}

\text{Ba}^{2+}, \text{Sr}^{2+}

\text{Sr}^{2+}, \text{Ca}^{2+}

\text{Ba}^{2+}, \text{Ca}^{2+}