Question

Two beakers A and B contain 100 g of water and 100 g of alcohol at ${70}^{0}C$. The total heat energy contained in beaker

• A. A is more than beaker B
• B. A is less than beaker B
• C. A and B is the same
• D. none of these

Answer 1

The correct option is A A is more than beaker B

Answer is A.

Water is denser than alcohol because the space between water molecules is less than the space between alcohol molecules. Hence, there is more matter per unit volume of water than per unit volume of alcohol. Since a unit volume of water contains more matter than an identical volume of alcohol, its density is greater.
The large number of molecules per unit of volume (density) of water means that the overall kinetic energy of all those molecules combined (heat) will also be large.
Hence, when two beakers A and B containing 100 g of water and 100 g of alcohol at 70 degree Celsius, the heat contained in A is more than the heat contained in beaker B.