A 6.50 molal solution of KOH (aq) has density of $1.89 g.cm^{-3} $. The molarity of solution is _ _ _ _ $mol.dm^{-3} $. (Round off to the nearest integer).
[Atomic masses: K = 39.0 u, O = 16.0 u, H = 1.0 u] Continue reading A 6.50 molal solution of KOH (aq) has density of $1.89 g.cm^{-3} $ ….
For the reaction $A(g) \rightleftharpoons B(g)$ at 495 K, $\Delta_r G^\circ = -9.478 kJ.mol^{-1} $. If we start the reaction in a closed container at 495 K with 22 millimoles of A, the amount of B in the equilibrium mixture is _ _ _ _ millimoles. (Round off to the nearest integer)
[$R=8.314 J.mol^{-1} .K^{-1} $; ln 10 = 2.303 ] Continue reading For the reaction $A(g) \rightleftharpoons B(g)$ at 495 K ….
$AB_2 $ is 10% dissociated in water to $A^{2+}$ and $B^-$. The boiling point of a 10.0 molal aqueous solution of $AB_2 $ is _ _ _ _ $^ \circ C $. (Round off to the nearest integer)
[Given: Molal elevation constant of water $K_b = 0.5 K.Kg.mol^{-1} $, boiling point of pure water = $100 ^\circ C $] Continue reading $AB_2 $ is 10% dissociated in water to $A^{2+}$ and $B^-$ ….
Two salts $A_2 X $ and MX have the same value of solubility product of $4.0 \times 10^ {-12} $. The ratio of their molar solubilities i.e. $\frac{{S({A_2}X)}}{{S(MX)}} =$ _ _ _ _ . (Round off to the nearest integer) Continue reading Two salts $A_2 X $ and MX have the same value of ….
When light of wavelength 248 nm falls on a metal of threshold energy 3.0 eV, the de-Broglie wavelength of emitted electron is _ _ _ _ $A^\circ $. (Round off to the nearest integer)
[Use $\sqrt 3 = 1.73$, $h=6.63 \times 10^{-34} Js$, $m_e = 9.1 \times 10^{-31} Kg $, $c = 3.0 \times 10^8 ms^{-1}$, $1 eV = 1.6 \times 10^{-19} J$] Continue reading When light of wavelength 248 nm falls on a metal ….
The decomposition of formic acid on gold surface follows first order kinetics. If the rate constant at 300 K is $1.0 \times 10^{-3} s^{-1} $ and the activation energy $E_a = 11.488 kJ.mol^{-1} $, the rate constant at 200 K is _ _ _ _ $\times 10^{-5} s^{-1} $. (Round off to the nearest integer)
[Given $R = 8.314 J mol^{-1} K^{-1} $] Continue reading The decomposition of formic acid on gold surface follows ….
Complete combustion of 750 g of an organic compound provides 420 g of $CO_2 $ and 210 g of $H_2 O $. The percentage composition of carbon and hydrogen in organic compound is 15.3 and _ _ _ _ respectively. (Round off to the nearest integer) Continue reading Complete combustion of 750 g of an organic compound ….
