Gas Constants & their values The Avogadro constant (NA) = 6.02 × 1023 particles per mole The molar gas constant or universal gas constant (R) = 8.31 J mol−1 K−1 The Boltzmann constant (kb) = 1.38 × 10−23 J K−1 Gas constants and their relationships For an ideal gas of n moles and N molecules:number […]

## How to derive the value of R (Universal Gas Constant)

The Combined Gas Law or Gas Equation is as follows: PV / T = constant (K) ……… (1) The value of this constant K changes if the volume of the gas changes. (so, not a constant actually) Hence, a new constant kb is brought in, so that K = N kb, where n = number […]

## Thermodynamics – Formula bank

In this post, we present 30 formulas from the Thermodynamics chapter (class 11 physics). This formula bank is going to help you to find the formulas in a single place. formulas from Thermodynamics

## Numerical problems on the first law of thermodynamics

In this post, we will solve a few numerical problems using the First Law of Thermodynamics. Numerical problems on first law of thermodynamics Question number 1) Complete the values in Table 1 (all values are in kJ). Note that: W = 6 kJ is the work done on the system. Solution: As per the data […]

## Molar form of Enthalpy equation – how to derive?

The Enthalpy equation is represented as ΔH = ΔU + pΔV …(1) where ΔU is the change in internal energy and ΔV is the change in volume of the system. The difference between ΔH and ΔU is not usually significant for solids and liquids. However, when the systems involve gases, the difference becomes significant. Here, […]

## Numerical problem – Calculating Internal Energy Change (𝚫U) for a Reaction (Thermodynamics chapter)

In this post, we will solve a numerical problem from the Thermodynamics chapter. We will use the enthalpy and internal energy equation. The goal of this numerical is to calculate Internal Energy Change (𝚫U) for a chemical Reaction to make ammonia. Numerical problem from the Thermodynamics chapter – with solution Question: The reaction of nitrogen […]

## Enthalpy – chemistry revision notes for class 11

Enthalpy of a system may be defined as the sum of the internal energy(U) and the product of its pressure(p) and volume(v). It is denoted by the symbol H and is given by: H = U + pV Getting the Heat Transfer equation (derivation) Change in the internal energy of a system is:ΔU= q + […]

## Thermodynamics – class 11 chemistry notes

This post covers Thermodynamics with class 11 chemistry notes. The branch of science which deals with the study of different forms of energy and their interconversion is called thermodynamics. Thermodynamics means the flow of heat. Thermodynamics is one of the fundamental subject in physical chemistry It’s a science of macroscopic properties i.e. properties of matter […]

## Thermodynamics Processes

In this post, we will cover a few important & frequently asked questions on Thermodynamics Processes. The state of a thermodynamic system can be changed by a process. In other words, a process gives the path or operation by which a system changes from one state to another. The process may be accompanied by an […]