the temperature & the pressureThe pressure in a constant-volume gas thermometer is 0.700 atm at 100 Celsius degree and 0.512 atm at 0 Celsius...

As the mass and volume of the gas in the thermometer is constant, the change in pressure of the gas is directly proportional to the rise of temperature. Stated in other words rise in pressure per degree rise in temperature is constant.

Given:

Pressure at 100 degrees Celsius = 0.700 atm

Pressure at 0 degrees Celsius = 0.512 atm

Therefore:

Rise in pressure for 100 degrees rise in temperature = 0.700 0.512 = 0.188 atm

Therefore:

Rise in temperature per degree Celsius rise in temperature = 0.188/100 = 0.00188 atm

Therefore:

Temperature in Celsius corresponding to any pressure p is equal to:

t = (p - p0)/(rise in pressure per degree Celsius temperature)

= (p - 0.512)/0.00188

Therefore temperature corresponding to pressure of 0.040:

= (0.040 - 0.512)/).00188 - 0.112/0.00188 = 59.57 degree Celsius.

Similarly, pressure p in atm at any given temperature t is given by:

p = p0 + t*(Rise in temperature per degree Celsius rise in temperature)

= 0.512 + t*0.00188

Therefore the pressure at 450 degree Celsius:

= 0.512 + 450*0.00188 = 0.512 + 0.846 = 1.358 atm