Question

Titanium tetrachloride (TiCl$_4$) reacts with THF to form an octahedral complex X under inert atmosphere at 25°C. If 5.0 g of TiCl$_4$ is used and the yield is 80%, the amount of X (in grams) formed is .......... (Round off to one decimal place) (Use atomic weights: Ti = 48, Cl = 35.5, O = 16, C = 12, H = 1)

Hint:

Always account for yield in reactions, as the actual amount of product will be less than the theoretical amount.

Answer 1

Correct Answer: 6.9 - 7.1

Reaction: TiCl₄ reacts with THF (tetrahydrofuran, C₄H₈O) to form an octahedral complex.

Complex formation: TiCl₄ + 2 THF → TiCl₄(THF)₂

This forms an octahedral complex where Ti is surrounded by 4 Cl atoms and 2 THF ligands (THF coordinates through oxygen).

Molecular weight calculations:

TiCl₄:

• Ti: 48
• Cl: 4 × 35.5 = 142
• Total = 48 + 142 = 190 g/mol

THF (C₄H₈O):

• C: 4 × 12 = 48
• H: 8 × 1 = 8
• O: 1 × 16 = 16
• Total = 48 + 8 + 16 = 72 g/mol

Complex X [TiCl₄(THF)₂]:

• TiCl₄: 190
• 2 THF: 2 × 72 = 144
• Total = 190 + 144 = 334 g/mol

Calculation:

Moles of TiCl₄ used = 5.0/190 = 0.02632 mol

Theoretical yield of X = 0.02632 × 334 = 8.79 g

Actual yield (80%) = 8.79 × 0.80 = 7.03 g

Answer: 7.0 g (rounded to one decimal place)