Question

Starting with 5.00 g barium chloride n hydrate yields 4.26 g of anhydrous barium chloride after heating. Determine the integer n.

Answer 1

BaCl₂·(H₂O)₂

Step-by-step explanation:

The reaction that takes place is:

• BaCl₂·(H₂O)ₙ → BaCl₂ + nH₂O

The information given by the problem tells us that 5.00 g of reactant were consumed. Of those 5.00 g, 4.26 g were converted into BaCl₂, this means that the other 0.74 g were converted into water.

We convert 0.74 g of water into moles, using its molar mass:

• 0.74 g H₂O ÷ 18 g/mol = 0.041 mol H₂O

Then we convert 4.26 g of BaCl₂ into moles:

• 4.26 g BaCl₂ ÷ 208.23 g/mol = 0.0204 mol BaCl₂

We can write these results as (BaCl₂)₀.₀₂·(H₂O)₀.₀₄. We multiply those coefficients by 50 in order to make them integers, and we're left with:

• BaCl₂·(H₂O)₂