General Science

The concentration of water molecules in the cell is higher than the concentration of water molecules in surrounding medium
The concentration of water molecules in surrounding medium is higher than water molecules concentration in the cell
The concentration of water molecules is same in the cell and in the surrounding medium
Concentration of water molecules does not matter

The first model of an atom was given by

GC Atomic Structure

The first model of an atom was given by

N. Bohr
E. Goldstein
Rutherford
J.J. Thomson

Elements with valency 1 are

GC Atomic Structure

Elements with valency 1 are

always metals
always metalloids
either metals or non-metals
always non-metals

The ion of an element has 3 positive charges

GC Atomic Structure

The ion of an element has 3 positive charges. Mass number of the atom is 27 and the number of neutrons is 14. What is the number of electrons in the ion?

In the Thomson’s model of atom, which statements are correct

GC Atomic Structure

In the Thomson’s model of atom, which of the following statements are correct?

the mass of the atom is assumed to be uniformly distributed over the atom
the positive charge is assumed to be uniformly distributed over the atom
the electrons are uniformly distributed in the positively charged sphere
the electrons attract each other to stabilise the atom

Select the correct option:

(i), (ii) and (iii)
(i) and (iii)
(i) and (iv)
(i), (iii) and (iv)

Which statements about Rutherford’s model of atom are correct

GC Atomic Structure

Which of the following statements about Rutherford’s model of atom are correct?

considered the nucleus as positively charged
established that the α–particles are four times as heavy as a hydrogen atom
can be compared to solar system
was in agreement with Thomson’s model

Select the correct option:

(i) and (iii)
(ii) and (iii)
(i) and (iv)
only (i)

Dalton’s atomic theory successfully explained

GC Atomic Structure

Dalton’s atomic theory successfully explained

Law of conservation of mass
Law of constant composition
Law of radioactivity
Law of multiple proportion

Select the correct option:

(i), (ii) and (iii)
(i), (iii) and (iv)
(ii), (iii) and (iv)
(i), (ii) and (iv)

The number of electrons in an element X is 15 and the number of neutrons is 16

GC Atomic Structure

The number of electrons in an element X is 15 and the number of neutrons is 16. Which of the following is the correct representation of the element?

³¹₁₅ X
³¹₁₆ X
¹⁶₁₅ X
¹⁵₁₆ X

Rutherford’s alpha (α) particles scattering experiment resulted

GC Atomic Structure

Rutherford’s ‘alpha (α) particles scattering experiment’ resulted in to discovery of

Electron
Proton
Nucleus in the atom
Atomic mass

Which represent the electronic distribution in the Mg atom

GC Atomic Structure

Which of the following correctly represent the electronic distribution in the Mg atom?

3, 8, 1
2, 8, 2
1, 8, 3
8, 2, 2

3.42 g of sucrose are dissolved in 18 g of water in a beaker

GC Atomic Structure

3.42 g of sucrose are dissolved in 18 g of water in a beaker. The number of oxygen atoms in the solution are

6.68 × 10²³
6.09 × 10²²
6.022 × 10²³
6.022 × 10²¹

Which of the following correctly represents 360 g of water?

GC Atomic Structure

Which of the following correctly represents 360 g of water?

2 moles of H₂O
20 moles of water
6.022 × 10²³ molecules of water
1.2044 × 10²⁵ molecules of water

Select the correct option:

(i)
(i) and (iv)
(ii) and (iii)
(ii) and (iv)

A mixture of sulphur and carbon disulphide is

GC Matter

A mixture of sulphur and carbon disulphide is

heterogeneous and shows Tyndall effect
homogeneous and shows Tyndall effect
heterogeneous and does not show Tyndall effect
homogeneous and does not show Tyndall effect

During summer, water kept in an earthen pot becomes cool because

GC Matter

During summer, water kept in an earthen pot becomes cool because of the phenomenon of

diffusion
transpiration
osmosis
evaporation

Which phenomena would increase on raising the temperature

GC Matter

Which one of the following sets of phenomena would increase on raising the temperature?

Diffusion, evaporation, compression of gases
Evaporation, compression of gases, solubility
Evaporation, diffusion, expansion of gases
Evaporation, solubility, diffusion, compression of gases

Potable water is the water which is

GS Water

Potable water is the water which is

obtained from a river
obtained from a lake
pure and fit for drinking
used only for washing clothes

Incomplete combustion of fuel such as petrol and diesel gives

GS Air

Incomplete combustion of fuel such as petrol and diesel gives

nitrogen oxide
sulphur dioxide
carbon monoxide
carbon dioxide

Two mirrors A and B are placed at right angles to each other

GP Light

Two mirrors A and B are placed at right angles to each other as shown in Figure.

A ray of light incident on mirror A at an angle of 25° falls on mirror B after reflection. The angle of reflection for the ray reflected from mirror B would be

25°
50°
65°
115°

A small hole P is made in a piece of cardboard

GP Light

A small hole P is made in a piece of cardboard. The hole is illuminated by a torch as shown in Figure. The pencil of light coming out of the hole falls on a mirror.