$A$ gas formed by the action of alcoholic $KOH$ on ethyl iodide,decolourises alkaline $KMnO_4$. The gas is

Calcium carbonate reacts with aqueous $HCl$ to give $CaCl_2$ and $CO_2$ according to the reaction given below: $CaCO_{3(s)} + 2HCl_{(aq)} \to CaCl_{2(aq)} + CO_{2(g)} + H_2O_{(l)}$
What mass of $CaCl_2$ will be formed when $250 \ mL$ of $0.76 \ M$ $HCl$ reacts with $1000 \ g$ of $CaCO_3$? Name the limiting reagent. Calculate the number of moles of $CaCl_2$ formed in the reaction.

For a Poisson variate $X$,if $P(X=2)=3 P(X=3)$,then the mean of $X$ is :

$A$ plank with a small block on top of it is undergoing vertical $SHM$. Its period is $2 \, s$. The minimum amplitude at which the block will separate from the plank is:

Which of the following factors favour the dissociation of $HbO_2$ at the tissue level?

Consider the situation shown in the figure. The wire $AB$ is sliding on the fixed rails with a constant velocity $v$. If the wire $AB$ is replaced by a semicircular wire of the same chord length,the magnitude of the induced current will