What amount of heat must be supplied to 2.0 × 10-2 kg of nitrogen (at room temperature) to raise its temperature by 45°C at constant pressure? (Molecular mass of N2 = 28; R = $$8.3 J mol^{-1} K^{-1}$$.)

Asked by Pragya Singh | 1 year ago |  130

##### Solution :-

Given,

Mass of nitrogen = 2 x 10-2 kg

= 20 g

Rise in temperature = ΔT

= 45°C

Heat required = Q =?

Q = nCT

We know,

C =$$\dfrac{7R}{2}$$ (diatomic molecule)

C = 7 x $$\dfrac{8.3}{2}$$

n (no. of moles) = $$\dfrac{w}{m}$$

where,

w = 20 g

m = 28 u

n = $$\dfrac{20}{28}$$

n = $$\dfrac{1}{1.4}$$ moles

Let the temperature be 45 K

Q = $$\dfrac{10}{14 \times \dfrac{7}{2} \times 8.3 \times 45}$$

We get,

Q = 933.75 J

Answered by Pragya Singh | 1 year ago

### Related Questions

#### A refrigerator is to maintain eatables kept inside at 9°C. If room temperature is 36°C, calculate the coefficient .

A refrigerator is to maintain eatables kept inside at 9°C. If room temperature is 36°C , calculate the coefficient of performance.

#### A thermodynamic system is taken from an original state to an intermediate state by the linear process shown in Fig.

A thermodynamic system is taken from an original state to an intermediate state by the linear process shown in Figure.

Its volume is then reduced to the original value from E to F by an isobaric process. Calculate the total work done by the gas from D to E to F

#### An electric heater supplies heat to a system at a rate of 100W.

An electric heater supplies heat to a system at a rate of 100W. If system performs work at a rate of 75 joules per second. At what rate is the internal energy increasing?

#### A steam engine delivers 5.4×108 J of work per minute and services 3.6 × 109 J of heat per minute from its boiler.

A steam engine delivers 5.4×108 J of work per minute and services 3.6 × 109 J of heat per minute from its boiler. What is the efficiency of the engine? How much heat is wasted per minute?

#### Two cylinders A and B of equal capacity are connected to each other via a stopcock.

Two cylinders A and B of equal capacity are connected to each other via a stopcock. A contains a gas at standard temperature and pressure. B is completely evacuated. The entire system is thermally insulated. The stopcock is suddenly opened. Answer the following:

(a) What is the final pressure of the gas in A and B?

(b) What is the change in internal energy of the gas?

(c) What is the change in the temperature of the gas?

(d) Do the intermediate states of the system (before settling to the final equilibrium state) lie on its P-V-T surface?