Atoms are too small with a diameter of 10^-10 m and weigh approximately ______________.

(a)

10^-27 kg

(b)

10^-27 g

(c)

10^-31 kg

(d)

10^-31

The fixed circular paths around the nucleus are caused ____

(a)

orbits

(b)

Orbitals

(c)

nucleons

(d)

Mesons

Which of the following is Dobereiner's triad?

(a)

Ne,Ca,Na

(b)

H₂, N₂, O₂

(c)

Li, Na, K

(d)

Na, Br, K

The atomic weight of Au is ______

(a)

195

(b)

197

(c)

198

(d)

196

The vertical columns in the periodic table are called as ___________

(a)

family

(b)

group

(c)

period

(d)

both (a) and (c)

______ is the lightest metal known.

(a)

Na

(b)

Li

(c)

Mg

(d)

Al

Which of the following does not have zero electron gain enthalpy?

(a)

Be

(b)

Cl

(c)

Mg

(d)

N

Which of the following statements related to the modern periodic table is incorrect?

(a)

The p-block has 6 columns, because a maximum of 6 electrons can occupy all the orbitals in a p-subshell.

(b)

The d-block has 8 columns, because a maximum of 8 electrons can occupy all the orbitals in a d-subshell.

(c)

Each block contairis a number of columns equal to the number of electrons that can occupy that subshell.

(d)

The block indicates value of azimuthal quantum number (1) for the last subshell that received electrons in building up the electronic configuration.

Among the following elements, which has the least electron affinity?

(a)

Phosphorous

(b)

Oxygen

(c)

Sulphur

(d)

Nitrogen

Which of the following mixture of gases is called water gas?

(a)

CO_2(g)+ H_2(g)

(b)

CO_(g)+ N_2(g)

(c)

CO_(g)+ H_2(g)

(d)

N_2(g)+ H_2(g)

In case of alkali metal halides, the ionic character increases in the order ____________

(a)

MF < MCI < MBr < MI

(b)

MI < MBr < MCI < MF

(c)

MI < MBr

(d)

none of these

Which of the following oxides is the most basic in nature?

(a)

Na₂O

(b)

BeO

(c)

Li₂O

(d)

H₂O

Which hydroxide decomposes on heating?

(a)

NaOH

(b)

RbOH

(c)

KOH

(d)

LiOH.

The radioactive element of group 2 element is ______

(a)

Strontium

(b)

Radium

(c)

Beryllium

(d)

Francium

_______ is unstable in air and is kept in CO₂ atmosphere to avoid decomposition.

(a)

BeCO₃

(b)

MgCO₃

(c)

CaCO₃

(d)

BaCO₃

Identify the correct statements about barium.
(i) It shows photoelectric effect
(ii) It is silvery white metal
(ill) It forms Ba(NO₃)₂ which is used in preparation of green tire

(a)

Both (i) and (iii)

(b)

(ii) and (iii)

(c)

Only (ii)

(d)

(i),(ii),(iii)

Gypsum is _________

(a)

CaSO₄.H₂O

(b)

CaSO₄.1/2H₂O

(c)

CaSO₄.1/4H₂O

(d)

CaSO₄.2H₂O

Celestite and strontianite are the ores of ______

(a)

cesium

(b)

strontium

(c)

magnesium

(d)

barium

Which metal is used in making electrochemical cells?

(a)

Caesium

(b)

Lithium

(c)

Calcium

(d)

Barium

Which one of the following is used for mercerising cotton fabrics?

(a)

KOH

(b)

NaOH

(c)

Na₂CO₃

(d)

NaHCO₃

Absolute zero is ________

(a)

-273^oC

(b)

0 K

(c)

temperature at which no substance exists in gaseous state

(d)

all of these

Identify the correct mathematical expression of Graham's law of diffusion __________

(a)

\(\frac { { r }_{ 2 } }{ { r }_{ 1 } } =\sqrt { \frac { { M }_{ 2 } }{ { M }_{ 1 } } } \)

(b)

\({ r }_{ 1 }r_{ 2 }=\sqrt { \frac { { M }_{ 2 } }{ { M }_{ 1 } } } \)

(c)

\(\frac { { r }_{ 1 } }{ { r }_{ 2 } } =\sqrt { \frac { { M }_{ 2 } }{ { M }_{ 1 } } } \)

(d)

\(\frac { { r }_{ 1 } }{ { r }_{ 2 } } ={ \left[ \frac { { M }_{ 2 } }{ { M }_{ 1 } } \right] }^{ 2 }\)

Equimolal aqueous solutions of NaCl and KCl are prepared. If the freezing point of NaCl is –2^oC, the freezing point of KCl solution is expected to be ____________

(a)

-2^oC

(b)

-4^oC

(c)

-1^oC

(d)

0^oC

Which one of the following is non aromatic?

(a)

(b)

(c)

(d)

Bhopal Gas Tragedy is a case of _____________.

(a)

thermal pollution

(b)

air pollution

(c)

nuclear pollution

(d)

land pollution