List of top Chemistry Questions

Buna-S is polymer of:

Red phosphorus is chemically less reactive than white phosphorus because :

Zinc displaces copper from copper sulphate solution. The $E^{\circ}_{298\, K}$ of $Zn$ is $-0.76 \,V$ and that of $Cu$ is $+0.34 \,V$.

Tailing of mercury occurs on passing ozone through it. Due to oxidation of mercury.

Lower aldehydes and ketones are soluble in water but the solubility decreases as the molecular masses increase. Distinction between aldehydes and ketones can be made by Tollens??test.

Pressure in a mixture of $4 \,g$ of $O _{2}$ and $2\, g$ of $H _{2}$ confined in a bulb of 1 litre at $0^{\circ} C$ is

Which of the following are ${ }_{16} S ^{32}$ and ${ }_{15} Pb ^{31}$ ?

Which of the following transition elements shows the highest oxidation state?

Which of the following has maximum ionisation potential?

The solubility in water of sulphates down the $Be$ group is $Be > Mg > Ca > Sr > Ba$. This is due to

Which of the following will not undergo hydrolysis in water?

Which of the following is the correct statement for $PH_3$ ?

Oxidation state of osmium (Os) in $OsO_4$ is

An element with atomic number $26$ will be found in group :

The covalent compound $ HCl $ has the ionic character as:

$ {{E}_{n}}=-\frac{313.6}{{{n}^{2}}} $ . If the value of $ {{E}_{n}}=-34.84 $ to which of the following values does $'n'$ correspond?

The constant $'a'$ in van der Wall's equation is maximum in :

The screening effect of $'d'$ electrons is:

The pressure of atmosphere air is $ 720\text{ }mm $ . The pressure of water vapour in the air is:

Principle/which gives a way to fill the electrons in the available energy levels is:

Pure propanone can be prepared by ozonolysis of:

Which compound is obtained when formaldehyde is treated with ammonia?

An example of anthraquinone dye is

Nylon-66 is made by using

Which of the following order for ionization energy is correct ?