5.4 Development of the Atomic Model

Who was Democritus?

• A Roman philosopher

• A Greek philosopher

• An Egyptian scientist

• A Persian mathematician

Who linked elements and atoms in simple ratios?

• JJ Thompson

• John Dalton

• Albert Einstein

• Niels Bohr

Who proposed the "plum pudding model"?

• John Dalton

• JJ Thompson

• Ernest Rutherford

• James Chadwick

What surrounds the negative 'plums' in the "plum pudding model"?

• Sea of positive 'pudding'

• Sea of negative 'pudding'

• Sea of neutral 'pudding'

• Sea of atomic 'pudding'

What did John Dalton contribute to the understanding of atoms?

• Discovery of electrons

• Linking elements and atoms in simple ratios

• Discovery of protons

• Development of quantum theory

What did JJ Thompson's discovery lead to in terms of atomic theory?

• Discovery of the neutron

• Understanding of atomic nuclei

• Identification of subatomic particles

• Development of the periodic table

What did Rutherford's experiment prove about the structure of the atom?

• Atoms are solid spheres

• Atoms are mostly empty space

• Atoms are made of water

• Atoms are indivisible

What did Bohr's model of the atom show about electrons?

• Electrons are stationary

• Electrons orbit the nucleus in fixed shells

• Electrons are inside the nucleus

• Electrons are randomly scattered

What is the charge of the nucleus according to Bohr's model?

• Neutral

• Positive

• Negative

• Variable

What did the moderate deflection of alpha particles in Rutherford's experiment suggest?

• The presence of a dense nucleus

• The presence of electrons

• The presence of neutrons

• The presence of protons