HF and HCN are both weak acids. Ka = 3.5 x 10-4 for HF Ka = 4.9 x 10-10 for HCN What is [CN-] in a mixture of 0.50 M HF and 0.30 M HCN. A. 1.2 × 10-5 M B. 7.4 × 10-6 M C. 2.4 × 10-10 M D. 1.1 × 10-8 M E. 3.7×10-6M

Constant Volume Calorimeter.

Explanation:

In order to measure the heat released in burning of a gasoline, we generally use closed calorimeter. It is a constant volume calorimter.

Most common example of such calorimter is Bomb calorimeter.

We use closed calorimter or constant volume calorimter as large amount of heat is released during combustion of a fuel or gasoline.