The air in a living room has a mass of 60 Kg and a specific heat of 1,020 J/kg°C. What is the change in thermal energy of the air when it warms from 20°C to 25°C?

Q = 306 kJ

Explanation:

Given that,

Mass, m = 60 kg

Specific heat, c = 1020 J/kg°C

The temperature changes from 20°C to 25°C.

Let Q be the change in thermal energy. The formula for the heat released is given by :

Put all the values,

So, 306 kJ is the change in thermal energy.

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol