Question

The formula for sodium sulfate is \(\mathrm{Na}_{2} \mathrm{SO}_{4}\). Write the names and formulas for the other alkali metal sulfates.

Short answer

Lithium sulfate: \( \text{Li}_2\text{SO}_4 \); Potassium sulfate: \( \text{K}_2\text{SO}_4 \); Rubidium sulfate: \( \text{Rb}_2\text{SO}_4 \); Cesium sulfate: \( \text{Cs}_2\text{SO}_4 \)

Step-by-step solution

- Understand the Formula for Sodium Sulfate

The formula for sodium sulfate is \( \mathrm{Na}_{2} \mathrm{SO}_{4} \). Here, sodium (Na) is the alkali metal.

- Identify Alkali Metals

The alkali metals include lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr). Sodium (Na) has already been given, so we will consider the others.

- Combine Alkali Metals with Sulfate Ion

For each alkali metal, combine the metal with the sulfate ion (\( \text{SO}_{4}^{2-} \)). The general formula will be \( \text{M}_2\text{SO}_4 \), where \( \text{M} \) is the alkali metal.

- Write the Formulas

Lithium sulfate: \( \text{Li}_2\text{SO}_4 \)Potassium sulfate: \( \text{K}_2\text{SO}_4 \)Rubidium sulfate: \( \text{Rb}_2\text{SO}_4 \)Cesium sulfate: \( \text{Cs}_2\text{SO}_4 \)

- Complete the Names and Formulas List

So the names and formulas for the other alkali metal sulfates are:Lithium sulfate: \( \text{Li}_2\text{SO}_4 \)Potassium sulfate: \( \text{K}_2\text{SO}_4 \)Rubidium sulfate: \( \text{Rb}_2\text{SO}_4 \)Cesium sulfate: \( \text{Cs}_2\text{SO}_4 \)

Key concepts

Chemical Formulas

Understanding chemical formulas is key in chemistry. A chemical formula shows the types and numbers of atoms in a molecule. For example, the formula \( \text{Na}_2\text{SO}_4 \), represents sodium sulfate. It tells us that there are 2 sodium (Na) atoms and one sulfate ion \( \text{SO}_4^{2-} \).
This balance of ions is essential to keep the compound neutral. Recognizing these patterns helps in writing formulas for similar compounds.
Practice by writing out different combinations of metals and non-metals, like alkali metals with sulfate ions.

Alkali Metals

Alkali metals belong to Group 1 of the periodic table. They include elements such as lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr).
These metals are highly reactive, especially with water, and they are characterized by having one electron in their outermost shell, which they easily lose to form positive ions (\text{M}^+).
Their reactivity increases down the group: lithium is less reactive than potassium, for example.
When combined with the sulfate ion, they form stable compounds like lithium sulfate \( \text{Li}_2\text{SO}_4 \) and cesium sulfate \( \text{Cs}_2\text{SO}_4 \).

Sulfate Ion

The sulfate ion (\text{SO}_4^{2-}) is a polyatomic ion with a -2 charge. It consists of one sulfur atom surrounded by four oxygen atoms in a tetrahedral arrangement.
Sulfate ions are common in many chemical compounds due to their stability and ability to form salts.
When combining with alkali metals, the formula typically takes the form of \( \text{M}_2\text{SO}_4 \), where \( \text{M} \) is the alkali metal.
Because alkali metals readily form \( \text{M}^+ \) ions, two alkali metal ions will balance one sulfate ion, resulting in neutral compounds like \( \text{K}_2\text{SO}_4 \) (potassium sulfate).

Inorganic Chemistry

Inorganic chemistry focuses on compounds that are not based on carbon-hydrogen bonds. This includes metals, salts, and minerals.
One major area is the study of ionic compounds, like those formed between alkali metals and sulfate ions.
Understanding the properties and reactions of these substances helps us in various fields, from industrial processes to materials science.
For example, knowing that alkali metals form strong electrolytes when dissolved in water helps us understand their role in chemical reactions and their practical applications, such as in batteries or fertilizers.