The metal used for the de-bromination reaction of $1, 2-dibromoethane$ is:

$6.023 \times 10^{22}$ molecules are present in $10 \text{ g}$ of a substance '$X$'. The molarity of a solution containing $5 \text{ g}$ of substance '$X$' in $2 \text{ L}$ solution is ........... $\times 10^{-3} \text{ M}$.

Which of the following kingdoms does Paramecium belong to?

In a permanent magnet at room temperature,

What is the correct relationship between the $pH$ values of isomolar solutions of sodium oxide $(pH_1)$,sodium sulphide $(pH_2)$,sodium selenide $(pH_3)$,and sodium telluride $(pH_4)$?

$A$ railway line is taken round a circular arc of radius $1000 \ m$,and is banked by raising the outer rail $h \ m$ above the inner rail. If the lateral force on the inner rail when a train travels round the curve at $10 \ ms^{-1}$ is equal to the lateral force on the outer rail when the train's speed is $20 \ ms^{-1}$,the value of $4g \tan \theta$ is equal to: (The distance between the rails is $1.5 \ m$).