When \(25 \mathrm{~g}\) of a non-volatile solute is dissolved in \(100 \mathrm{~g}\) of water, the vapour pressure is lowered by \(2.25 \times 10^{-1} \mathrm{~mm}\). If the vapour pressure of water at \(20^{\circ} \mathrm{C}\) is \(17.5 \mathrm{~mm}\), what is the molecular weight of the solute?

The basicity of \(\mathrm{H}_3 \mathrm{PO}_2, \mathrm{H}_3 \mathrm{PO}_3, \mathrm{H}_3 \mathrm{PO}_4\) respectively is

The chlorination of ethane is an example for which type of the following reactions?

At 300 K . the \(E_{\text {cell }}^{\circ}\) of
\(\mathrm{A}(\mathrm{~s})+\mathrm{B}^{2+}(\mathrm{aq}) \rightleftharpoons \mathrm{A}^{2+}(\mathrm{aq})+\mathrm{B}(\mathrm{~s})\)
is 1.0 V . If \(\Delta_r S^{\circ}\) of this reaction is \(100 \mathrm{JK}^{-1}\), what is \(\Delta_{\mathrm{r}} \mathrm{H}^{\circ}\)
(in \(\mathrm{kJ} \mathrm{mol}^{-1}\) ) of this reaction?( \(\mathrm{F}=96500 \mathrm{Cmol}^{-1}\) )

An element with mass number $181$ contains $32\%$ more neutrons as compared to protons. What is the symbol of that element?

Match the following
\(\begin{array}{|c|c|c|}
\hline & \text { List - I } & & \text { List - II } \\
\hline \text{b)} & \text { Vitamin } \mathrm{E} & \text { i) } & \text { Meat } \\
\hline \text{c)} & \text { Vitamin K } & \text { ii) } & \text { Sunflower oil } \\
\hline \text{d)} & \text { Vitamin } B_{12} & \text { iii) } & \text { Egg white } \\
\hline \text{e)} & \text { Vitamin } B_2 & \text { iv) } & \text { Exposure to sunlight } \\
\hline & & \text { v) } & \text { Green leafy vegetables } \\
\hline
\end{array}\)
The correct answer is

Which of the following ions can reduce dilute acid to give hydrogen gas?

In triangle \(A B C\), if \(\frac{b+c}{9}=\frac{c+a}{10}=\frac{a+b}{11}\), then \(\frac{\cos A+\cos B}{\cos C}=\)

The value of ${}^{6}P_4+4·{}^{6}P_3$ is ______.

Which of the following property is less for \(\mathrm{D}_2 \mathrm{O}\) than \(\mathrm{H}_2 \mathrm{O}\) ?

The value of the sum \(1 \times 2 \times 3+2 \times 3 \times 4+3 \times 4 \times 5+\ldots\) upto \(n\) terms is equal to

As shown in the figure, two infinitely long straight parallel wires \(P\) and \(Q\) carrying equal currents in opposite directions are arranged parallel to \(\mathrm{Y}\)-axis. If the magnetic field due to wire \(\mathrm{P}\) at the origin ' \(\mathrm{O}\) ' of the co-ordinate system is B, then match the resultant magnetic fields at various points given in column \(A\) with the points given in column \(B\).
\(\begin{array}{ll}
\text{Column A} & \text{Column B} \\
\text{A)} \frac{B}{4} & \text{i)} (0,0) \\
\text{B)} \frac{B}{2} & \text{ii)} (a, 0) \\
\text{C)} \frac{2 \mathrm{~B}}{3} & \text{iii)} (2a, 0) \\
\text{D)} 2 \mathrm{~B} & \text{iv)} (3 \mathrm{a}, 0) \\
\end{array}\)


The correct answer is

Three amplifiers with voltage gains 10,20 and 30 are connected in series. If the input signal has a peak value of \(1 \mathrm{mV}\) then the peak value of the output voltage is