#1
Who proposed the plum pudding model of the atom?
J.J. Thomson
ExplanationThomson suggested electrons embedded in a positively charged sphere.
#2
What is the name of the model that suggests electrons move in fixed orbits around the nucleus?
Bohr Model
ExplanationBohr's model postulated discrete electron orbits, akin to planets orbiting the sun.
#3
What is the charge of an electron?
Negative
ExplanationElectrons possess a negative electrical charge.
#4
Who discovered the nucleus of an atom?
Ernest Rutherford
ExplanationRutherford's gold foil experiment led to the discovery of the atomic nucleus.
#5
What is the maximum number of electrons that can occupy the first shell of an atom?
2
ExplanationThe first shell can hold a maximum of two electrons.
#6
Who proposed the planetary model of the atom?
Niels Bohr
ExplanationBohr's model conceptualized electrons orbiting the nucleus in fixed paths.
#7
What is the charge of a proton?
Positive
ExplanationProtons carry a positive electrical charge.
#8
What is the charge of a neutron?
Neutral
ExplanationNeutrons have no net electrical charge.
#9
What does the atomic number of an element represent?
Number of protons
ExplanationAtomic number indicates the quantity of protons in an atom's nucleus.
#10
Who proposed the concept of electron shells or energy levels?
Niels Bohr
ExplanationBohr introduced the idea of electrons occupying specific energy levels.
#11
Who proposed the quantum mechanical model of the atom?
Erwin Schrödinger
ExplanationSchrödinger formulated a model describing electron probability distributions.
#12
What is the name of the model that describes the atom as mostly empty space with a dense nucleus at its center?
Rutherford Model
ExplanationRutherford's model depicted atoms as having a dense central nucleus.
#13
Who proposed the concept of the wave-particle duality of matter?
Louis de Broglie
ExplanationDe Broglie suggested matter can exhibit both wave and particle properties.
#14
What is the modern description of the arrangement of electrons in an atom?
Quantum Mechanical Model
ExplanationThis model describes electrons' probable locations around the nucleus.
#15
Which scientist introduced the concept of the uncertainty principle?
Werner Heisenberg
ExplanationHeisenberg's principle states inherent limits in measuring certain pairs of properties.