What is the central part of an atom called?
a) Electron
b) Proton
c) Neutron
d) Nucleus
What particles are found in the nucleus of an atom?
a) Protons and electrons
b) Protons and neutrons
c) Neutrons and electrons
d) Protons, neutrons, and electrons
Which particle has a negative charge?
a) Proton
b) Neutron
c) Electron
d) Nucleus
What is the charge of a proton?
a) Positive
b) Negative
c) Neutral
d) Undefined
What is the charge of a neutron?
a) Positive
b) Negative
c) Neutral
d) Undefined
Where are electrons located in an atom?
a) In the nucleus
b) In the electron cloud around the nucleus
c) In the protons
d) In the neutrons
Which of the following determines the atomic number of an element?
a) Number of neutrons
b) Number of electrons
c) Number of protons
d) Number of protons and neutrons
What is the mass of an electron compared to a proton?
a) Equal
b) Slightly greater
c) Much smaller
d) Much larger
Which model of the atom describes electrons moving in fixed orbits?
a) Bohr model
b) Rutherford model
c) Quantum model
d) Thomson model
What is the atomic mass of an atom mostly determined by?
a) Number of electrons
b) Number of protons and neutrons
c) Number of neutrons
d) Number of protons
Which subatomic particle has a mass approximately 1 amu?
a) Electron
b) Neutron
c) Proton
d) Both b and c
Which subatomic particle has a positive charge?
a) Neutron
b) Proton
c) Electron
d) Photon
What is the Bohr model of the atom based on?
a) Electron cloud theory
b) Electrons orbiting the nucleus in fixed paths
c) Neutrons revolving around protons
d) Electrons in random positions
How is the number of neutrons in an atom calculated?
a) By subtracting the atomic number from the atomic mass number
b) By adding the number of protons and electrons
c) By subtracting the number of protons from the number of electrons
d) By adding the number of neutrons and protons
What is an isotope of an element?
a) Atoms with the same number of protons but different number of neutrons
b) Atoms with the same number of neutrons but different number of protons
c) Atoms with the same number of electrons and protons
d) Atoms of different elements with the same mass number
Which of the following best describes the electron cloud model of the atom?
a) Electrons travel in fixed orbits around the nucleus
b) Electrons are evenly distributed throughout the atom
c) Electrons move in random positions around the nucleus
d) Electrons are fixed in position around the nucleus
What does the atomic number of an element represent?
a) The total number of electrons
b) The total number of protons
c) The sum of protons and neutrons
d) The average number of neutrons
What happens when an electron moves to a higher energy level in an atom?
a) It releases energy as light
b) It absorbs energy
c) It becomes neutral
d) It decays
What is the atomic mass unit (amu) used to measure?
a) The mass of an atom
b) The charge of a proton
c) The mass of a photon
d) The energy of an electron
What is the name of the particle discovered by J.J. Thomson that led to the discovery of the electron?
a) Proton
b) Electron
c) Neutron
d) Photon
Which of the following particles was discovered using the gold foil experiment?
a) Proton
b) Neutron
c) Electron
d) Nucleus
What does the Rutherford model of the atom describe?
a) Electrons are spread out in the atom
b) The atom is mostly empty space with a dense nucleus
c) Electrons revolve around the nucleus in fixed orbits
d) Electrons do not exist in definite orbits
Which of the following describes a neutron’s role in the atom?
a) It balances the positive charge of protons
b) It carries a positive charge
c) It carries a negative charge
d) It determines the element’s atomic number
What is the electron configuration of a neutral oxygen atom (atomic number 8)?
a) 2, 6
b) 2, 8
c) 4, 4
d) 1, 7
How many electrons can be in the second energy level of an atom?
a) 2
b) 4
c) 8
d) 18
Which subatomic particle determines the identity of an element?
a) Neutron
b) Electron
c) Proton
d) Photon
What does the quantum mechanical model of the atom describe?
a) Electrons in fixed orbits
b) Electrons in random motion within probability clouds
c) Electrons at rest in the nucleus
d) Electrons in fixed positions around the nucleus
What is the maximum number of electrons that can occupy the first energy level of an atom?
a) 2
b) 4
c) 8
d) 18
Which element has an atomic number of 6?
a) Oxygen
b) Carbon
c) Nitrogen
d) Hydrogen
How does the mass of a neutron compare to the mass of a proton?
a) Neutron is heavier
b) Neutron is lighter
c) Neutron has the same mass
d) Neutron has no mass
