Question

A tangent drawn on the curve obtained by plotting concentration of product ( mole $L^{-1}$) of the first-order reaction vs time (min) at the point corresponding to time minute takes an angle to ${30}^{\circ }$ with concentration axis Hence the rate of formations of product after 20 minutes will be:

• A. 0.580 mole $L^{-1}mi{n}^{-1}$
• B. 1.723 mole $L^{-1}mi{n}^{-1}$
• C. 0.290 mole $L^{-1}mi{n}^{-1}$
• D. 0.866 mole $L^{-1}mi{n}^{-1}$

Answer 1

The correct option is B 1.723 mole $L^{-1}mi{n}^{-1}$

Tangent makes an angle of ${30}^{\circ }$ with concentration axis so it must make an angle of ${60}^{\circ }$ with the time axis (-ve direction) The slope of the tangent will be tan ${60}^{\circ }$ with the time axis (-av direction) The slope of the tangent will be tan ${60}^{\circ }$ i.e. 1.723