A sample of sand initially at 22.2 °C absorbs 1364 J of heat. The final temperature of the sand is 67 °C. What is the mass (in g) of sand in the sample? The heat capacity of sand is 0.84

The mass of sand in the sample is 36.24 grams.

Explanation:

The equation used to calculate heat released or absorbed follows:

where,

q = heat absorbed = 1364 J

m = mass of sand = ?

c = heat capacity of sand = 0.84 J/g°C

= initial temperature = 22.2°C

= final temperature = 67°C

Putting values in above equation, we get:

Hence, the mass of sand in the sample is 36.24 grams.

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.