Crude oil is subjected to vacuum distillation in the last stage, because_________________?

Crude oil is subjected to vacuum distillation in the last stage, because_________________?

A. High boiling point products like heavy fuel oil & lubricating oils are heat sensitive and may
decompose

B. Lighter/low boiling products are prone to thermal decomposition
C. High purity products can be obtained thereby
D. None of these

Hydrogen content in petroleum products varies from 12 to 15% (by weight). As a result the difference between gross and net heating value of petroleum fuels varies in the range of ______________ kcal/kg?

Hydrogen content in petroleum products varies from 12 to 15% (by weight). As a result the difference between gross and net heating value of petroleum fuels varies in the range of ______________ kcal/kg?

A. 600-750
B. 250-350
C. 1000-1500
D. 2000-2500