GC Atomic Structure

The mass number of an atom is determined by

The mass number of an atom is determined by

1. the number of protons only
2. adding the number of neutrons and number of electrons
3. adding the number of protons and number of electrons
4. adding the number of neutrons and number of protons

Which of the following pairs represents isoelectronic ions

Which of the following pairs represents isoelectronic ions

1. Mg²⁺, Ca²⁺
2. Na⁺, K⁺
3. K⁺, Mg²⁺
4. Ca²⁺, S^2-

Which one among the following contains the most neutrons

Which one among the following contains the most neutrons?

1. ⁶¹₂₉Cu
2. ⁵⁹₂₆Fe
3. ⁶⁰₃₀Zn²⁺
4. ⁶¹₃₀Zn

Two atoms are said to be isotopes if

Two atoms are said to be isotopes if

1. they have the same atomic number but different mass numbers
2. the sum of the number of protons and neutrons is the same, but the number of protons is different
3. they have the same number of neutrons but different modes of radioactive decay
4. they have the same number of neutrons but different mass numbers

The number of aluminium ions present in 54 g of aluminium

The number of aluminium ions present in 54 g of aluminium (atomic weight 27) is

1. 2
2. 18
3. 1.2 x 10²⁴
4. 1.1 x 10²⁴

Which one of the following is the correct electronic configuration of chlorine

Which one of the following is the correct electronic configuration of chlorine

1. 2, 8, 8
2. 2, 7, 8
3. 7, 8, 2
4. 2, 8, 7

The most of the mass of the atom can be found in

The most of the mass of the atom can be found in

1. nucleus
2. electron cloud
3. charges
4. electrons

The number of valence electrons in the O2- ion is

The number of valence electrons in the O^2- ion is

1. 4
2. 6
3. 8
4. 10

How many grams of MgCO3 contain 24.00 g of oxygen

How many grams of MgCO₃ contain 24.00 g of oxygen? (The molar mass of MgCO₃ is 84.30 g mol^–1)

1. 42.15 g
2. 84.30 g
3. 126.00 g
4. 154.00 g

Which is the correct electronic configuration of chlorine

Which one of the following is the correct electronic configuration of chlorine

1. 7, 8, 2
2. 2, 8, 7
3. 2, 8, 8
4. 2, 7, 8

The distribution of electrons into different orbits of an atom

The distribution of electrons into different orbits of an atom, as suggested by Bohr, is

1. 2 electrons in the K-orbit, 8 electrons in the L-orbit, 32 electrons in the M-orbit
2. 2 electrons in the K-orbit, 8 electrons in the L-orbit, 16 electrons in the M-orbit
3. 2 electron in the K-orbit, 6 electrons in the L-orbit, 18 electrons in the M-orbit
4. 2 electrons in the K-orbit, 8 electrons in the L-orbit, 18 electrons in the M-orbit

How much CO2 is produced on heating of 1 kg of carbon

How much CO₂ is produced on heating of 1 kg of carbon?

1. 11/3 kg 
2. 3/11 kg
3. 4/3 kg
4. 3/4 kg

The compound C6H12O4 contains

The compound C₆H₁₂O₄ contains

1. 22 atoms per mole
2. twice the mass percent of H as compared to the mass percent of C
3. six times the mass percent of C as compared to the mass percent of H
4. thrice the mass percent of H as compared to the mass percent of 0

The ionization energy of hydrogen atom in the ground state is

The ionization energy of hydrogen atom in the ground state is

1. 13.6 MeV
2. 13.6 eV
3. 13.6 Joule
4. Zero

Electron emission from a metallic surface by application of light

Electron emission from a metallic surface by application of light is known as

1. Thermionic emission
2. Photoelectric emission
3. High field emission
4. Autoelectronic emission

The first model of an atom was given by

The first model of an atom was given by

1. N. Bohr
2. E. Goldstein
3. Rutherford
4. J.J. Thomson

Elements with valency 1 are

Elements with valency 1 are

1. always metals
2. always metalloids
3. either metals or non-metals
4. always non-metals

The ion of an element has 3 positive charges

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?

1. 13
2. 10
3. 14
4. 16

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

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

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

Select the correct option:

1. (i), (ii) and (iii)
2. (i) and (iii)
3. (i) and (iv)
4. (i), (iii) and (iv)

Which statements about Rutherford’s model of atom are correct

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

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

Select the correct option:

1. (i) and (iii)
2. (ii) and (iii)
3. (i) and (iv)
4. only (i)

Dalton’s atomic theory successfully explained

Dalton’s atomic theory successfully explained

1. Law of conservation of mass
2. Law of constant composition
3.  Law of radioactivity
4. Law of multiple proportion

Select the correct option:

1. (i), (ii) and (iii)
2. (i), (iii) and (iv)
3. (ii), (iii) and (iv)
4. (i), (ii) and (iv)

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

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?

1. ³¹₁₅ X
2. ³¹₁₆ X
3. ¹⁶₁₅ X
4. ¹⁵₁₆ X

Rutherford’s alpha (α) particles scattering experiment resulted

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

1. Electron
2. Proton
3. Nucleus in the atom
4. Atomic mass

Which represent the electronic distribution in the Mg atom

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

1. 3, 8, 1
2. 2, 8, 2
3. 1, 8, 3
4. 8, 2, 2

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

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

1. 6.68 × 10²³
2. 6.09 × 10²²
3. 6.022 × 10²³
4. 6.022 × 10²¹

Which of the following correctly represents 360 g of water?

Which of the following correctly represents 360 g of water?

1. 2 moles of H₂O
2. 20 moles of water
3. 6.022 × 10²³ molecules of water
4. 1.2044 × 10²⁵ molecules of water

Select the correct option:

1. (i)
2. (i) and (iv)
3. (ii) and (iii)
4. (ii) and (iv)