To determine the oxidation number of the sulfur atom in [tex]\( Li_2SO_4 \)[/tex], follow these steps:
1. Identify the oxidation numbers of known elements:
- Lithium ([tex]\( Li \)[/tex]) typically has an oxidation number of [tex]\( +1 \)[/tex].
- Oxygen ([tex]\( O \)[/tex]) generally has an oxidation number of [tex]\( -2 \)[/tex].
2. Calculate the total oxidation numbers contributed by lithium and oxygen:
- There are 2 lithium atoms, so the total oxidation number from lithium is [tex]\( 2 \times +1 = +2 \)[/tex].
- There are 4 oxygen atoms, so the total oxidation number from oxygen is [tex]\( 4 \times -2 = -8 \)[/tex].
3. Express the sum of oxidation numbers in the compound:
- Let [tex]\( x \)[/tex] be the oxidation number of the sulfur atom.
- The compound [tex]\( Li_2SO_4 \)[/tex] is neutral, so the sum of the oxidation numbers of all atoms should be zero.
4. Set up the equation based on the sum of oxidation numbers:
[tex]\[
2 \times (+1) + 1 \times x + 4 \times (-2) = 0
\][/tex]
5. Solve the equation for [tex]\( x \)[/tex]:
[tex]\[
+2 + x - 8 = 0
\][/tex]
[tex]\[
x - 6 = 0
\][/tex]
[tex]\[
x = +6
\][/tex]
Thus, the oxidation number of the sulfur atom in [tex]\( Li_2SO_4 \)[/tex] is [tex]\( +6 \)[/tex].
So, the correct answer is:
[tex]\[ +6 \][/tex]
