What is a Balanced equation for sulfur (IV) oxide (g) and magnesium oxide (cr)?

SO2 + MgO(aq) ==> MgSO3

I don't know what you mean by MgO(cr).

To write a balanced equation for the reaction between sulfur (IV) oxide gas (SO2) and magnesium oxide solid (MgO), we'll need to follow a few steps:

Step 1: Write the formulas for the reactants and products based on their chemical symbols:

Sulfur (IV) oxide gas: SO2
Magnesium oxide solid: MgO

Step 2: Balance the equation by ensuring that the same number of atoms of each element is present on both sides of the equation. This is done by adjusting the coefficients (numbers in front of each compound):

SO2 + MgO → ?

Step 3: Check the number of atoms on each side of the equation:

On the left side:
Sulfur (S): 1
Oxygen (O): 2
Magnesium (Mg): 0

On the right side:
Sulfur (S): 1
Oxygen (O): 1
Magnesium (Mg): 1

Step 4: Balance the equation by adjusting the coefficients:

SO2 + MgO → MgSO3

Now the equation is balanced, and it shows that sulfur (IV) oxide gas reacts with magnesium oxide solid to produce magnesium sulfite.

The balanced equation is:
SO2 + MgO → MgSO3

The balanced equation for the reaction between sulfur (IV) oxide (g) and magnesium oxide (cr) can be represented as:

SO2 (g) + 2 MgO (cr) -> 2 MgSO3 (s)

In this reaction, sulfur dioxide reacts with magnesium oxide to produce magnesium sulfite as a solid product.