Calculate the molar mass of non volatile solute when 1 g of it is dissolved in 100 g solvent decreases its freezing point by 0.2 K . $\left[\mathrm{K}_{\mathrm{f}}=1.2 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right]$

Which from following statements is NOT true about lyophilic colloids?

Calculate the pH of a buffer solution containing 0.35 M weak acid and 0.70 M of its salt with strong base if $\mathrm{pK}_{\mathrm{a}}$ is 4.56 .

Which of the following alkenes does NOT exhibit cis-trans isomerism?