Question

No spam or lazy answers =_=

Answer 1

First see the given values

n = 5
dQ = 2500 - 1500
= 1000
since it is monoatomic gas and it is expanding so it is at constant pressure

so for monoatomic gas
cp = 5/2 R
intitial temp = 150 c = 150 + 273 = 423k
let final temp be "t"
so dT = t - 423

we know that
dQ = dU + dw
n*cp*dT = n*cv*dT + pdV.......(1)

since the volume is not constant so
n*cv*dT = 0

so eqn (1) can be modified as

n*cp*dT = pdV
5*5/2 R *(t - 423) = 2500

5/2 *8.314 (t - 423) = 2500 ÷ 5

20.785(t - 423) = 500
t - 423 = 500 ÷ 20.785
t - 423 = 24
t = 423 + 24
t = 447k
now convert kelvin into degree celcious
t = 447 - 273
t = 174

it is the answer hope it helps.