Which of the following is a hydride?

Which of the following is $NOT$ a characteristic of chemisorption?

$A$ fire hydrant delivers water of density $\rho$ at a volume rate $L$. The water travels vertically upward through the hydrant and then makes a $90^o$ turn to emerge horizontally at speed $V$. The pipe and nozzle have a uniform cross-section throughout. The force exerted by the water on the corner of the hydrant is

$A$ weightless thread can bear a tension up to $3.7\,kg-wt$. $A$ stone of mass $500\,g$ is tied to it and revolved in a circular path of radius $4\,m$ in a vertical plane. If $g = 10\,ms^{-2}$,then the maximum angular velocity of the stone will be ......... $rad\,s^{-1}$

How many $H$ atoms are present in $0.046 \, g$ of ethanol $(C_2H_5OH)$?

In which of the following is the alternation of generations $NOT$ observed?