The maximum and minimum melting points of the first and second transition series elements,respectively,are obtained with:

In a reaction $N_{2(g)} + 3H_{2(g)} \to 2NH_{3(g)}$,the rate of appearance of $NH_3$ is $2.5 \times 10^{-4} \, mol \, L^{-1} \, s^{-1}$. The rate of reaction and rate of disappearance of $H_2$ will be (in $mol \, L^{-1} \, s^{-1}$):

On a new scale of temperature (which is linear) called the $W$ scale,the freezing and boiling points of water are $39\,^{\circ}W$ and $239\,^{\circ}W$ respectively. What will be the temperature on the new scale,corresponding to a temperature of $39\,^{\circ}C$ on the Celsius scale? ............ $^{\circ}W$

If the ratio of diameters,lengths and Young's moduli of steel and brass wires shown in the figure are $p, q$ and $r$ respectively,then the corresponding ratio of increase in their lengths would be

Which of the following does not contain any co-ordinate bond?

Identify the blank spaces $a, b, c$ and $d$ given in the following table and select the correct answer.

Type of microbes	Scientific name	Commercial product
Bacterium	$a$	Clot buster
$b$	Aspergillus niger	Citric acid
Fungus	Trichoderma polysporum	$c$
Bacterium	$d$	Butyric acid