According to the following figure, the magnitude of the enthalpy change of the reaction $\mathrm{A}+\mathrm{B} \rightarrow \mathrm{M}+\mathrm{N}$ in kJ mol${ }^{-1}$ is equal to \_\_\_\_ . (Integer answer)

JEE Main · 2021 · 31 Aug 2021 · Shift 1 · Chemical Thermodynamics

According to the following figure, the magnitude of the enthalpy change of the reaction

A + B \to M + N

in kJ mol

^{- 1}

is equal to ____ . (Integer answer)

Answer: 45

The reactant level

A + B

is set by the dashed line, and the segment

y = 45 kJ mo l^{- 1}

measures how far the products

M + N

lie below it. The enthalpy change is the product level minus the reactant level,

Δ H = - 45 kJ mo l^{- 1}

; the activation height

x

and the offset

z

do not enter this difference. The magnitude of the enthalpy change is

45 kJ mo l^{- 1}

JEE Main · 2021 · 31 Aug 2021 · Shift 1 · Integer answer