JEE Main 2022 · 30 Jun · Shift 1 · Chemistry Q67

ChemistrySingle correct+4 / -1Question 67 of 90

$\Delta G^\circ$ vs T plot for the formation of MgO, involving reaction $\mathrm{2Mg+O_2\rightarrow2MgO}$ , will look like :

Rising line with a steeper rise after a break

Single straight rising line

Rising line that becomes flat after a break

Rising then falling line

Answer and worked solution

Official answer: A

Ellingham line for MgO rises with T (ΔS negative) and becomes steeper where Mg melts and boils, as entropy loss grows.

(A)

Topics:Extraction and thermodynamics (Ellingham)

JEE Main 2022 · 30 Jun · Shift 1, Chemistry question 67