Advertisements
Advertisements
प्रश्न
In Joly's differential steam calorimeter, 3 g of an ideal gas is contained in a rigid closed sphere at 20°C. The sphere is heated by steam at 100°C and it is found that an extra 0.095 g of steam has condensed into water as the temperature of the gas becomes constant. Calculate the specific heat capacity of the gas in J g−1 K−1. The latent heat of vaporisation of water = 540 cal g−1
Advertisements
उत्तर
For Joly's differential steam calorimeter,
`"C"_"v" = ("m"_2"L")/"m"_1 (theta _ 2 - theta_1),`
where
m2 = mass of steam condensed
m2 = 0.095 g
Latent heat of vapourization, L = 540 cal/g = 540 × 4.2 J/g
m1 = mass of gas present
m1 = 3 g
Initial temperature, θ1 = 20°C
Final temperature, θ2 = 100°C
`=> "C"_"v" = (0.095 xx 540 xx 4.2)/(3 xx (100-20)`
= 0.89 = 0.9 J/ g-K
APPEARS IN
संबंधित प्रश्न
The specific heat capacity of water is
Does a gas have just two specific heat capacities or more than two? Is the number of specific heat capacities of a gas countable?
Can we define specific heat capacity at constant temperature?
Can we define specific heat capacity for an adiabatic process?
In a real gas, the internal energy depends on temperature and also on volume. The energy increases when the gas expands isothermally. Examining the derivation of Cp − Cv = R, find whether Cp − Cv will be more than R, less than R or equal to R for a real gas.
Show that the slope of the p−V diagram is greater for an adiabatic process compared to an isothermal process.
Can two states of an ideal gas be connected by an isothermal process as well as an adiabatic process?
Two samples A and B are initially kept in the same state. Sample A is expanded through an adiabatic process and the sample B through an isothermal process. The final volumes of the samples are the same. The final pressures in A and B are pA and pBrespectively.
Let ∆Wa and ∆Wb be the work done by the systems A and B, respectively, in the previous question.
Consider the processes A and B shown in the figure. It is possible that
Three identical adiabatic containers A, B and C contain helium, neon and oxygen, respectively, at equal pressure. The gases are pushed to half their original volumes.
(a) The final temperatures in the three containers will be the same.
(b) The final pressures in the three containers will be the same.
(c) The pressures of helium and neon will be the same but that of oxygen will be different.
(d) The temperatures of helium and neon will be the same but that of oxygen will be different.
5 g of a gas is contained in a rigid container and is heated from 15°C to 25°C. Specific heat capacity of the gas at constant volume is 0.172 cal g−1 °C−1 and the mechanical equivalent of heat is 4.2 J cal−1. Calculate the change in the internal energy of the gas
A mixture contains 1 mole of helium (Cp = 2.5 R, Cv = 1.5 R) and 1 mole of hydrogen (Cp= 3.5 R, Cv = 2.5 R). Calculate the values of Cp, Cv and γ for the mixture.
The figure shows two vessels with adiabatic walls, one containing 0.1 g of helium (γ = 1.67, M = 4 g mol−1) and the other containing some amount of hydrogen (γ = 1.4, M = 2 g mol−1). Initially, the temperatures of the two gases are equal. The gases are electrically heated for some time during which equal amounts of heat are given to the two gases. It is found that the temperatures rise through the same amount in the two vessels. Calculate the mass of hydrogen.
The speed of sound in hydrogen at 0°C is 1280 m s−1. The density of hydrogen at STP is 0.089 kg m−3. Calculate the molar heat capacities Cp and Cv of hydrogen.
Standing waves of frequency 5.0 kHz are produced in a tube filled with oxygen at 300 K. The separation between the consecutive nodes is 3.3 cm. Calculate the specific heat capacities Cp and Cv of the gas.
If at same temperature and pressure, the densities for two diatomic gases are respectively d1 and d2 then the ratio of velocities of sound in these gases will be ______.
