Who first proposed that matter might be made of tiny solid balls called atoms?

• John Dalton

• Democritus

• JJ Thompson

• Ernest Rutherford

What did John Dalton suggest about elements and atoms?

• Atoms are made of smaller particles

• Atoms are indivisible

• Atoms are solid spheres

• Each element has its own type of atom

What significant discovery did JJ Thompson make in 1897?

• Atoms have a nucleus

• Atoms are solid spheres

• Atoms contain smaller particles called electrons

• Atoms are indivisible

What was the Plum Pudding model?

• A model where electrons orbit the nucleus

• A model where atoms are solid spheres

• A model where electrons are embedded in a positive charge

• A model where atoms are made of protons and neutrons

What did Rutherford's Alpha scattering experiment demonstrate?

• Atoms are indivisible

• Atoms contain electrons in fixed orbits

• Atoms have a dense, positive nucleus

• Atoms are solid spheres

According to Rutherford, why must the nucleus be very small?

• Because it is made of quarks

• Because it contains electrons

• Because most alpha particles pass through without deflection

• Because it is very light

What problem did Niels Bohr address with his atomic model?

• The existence of protons

• The discovery of neutrons

• The collapse of atoms due to energy loss

• The indivisibility of atoms

How did Bohr prevent atoms from collapsing in his model?

• By discovering neutrons

• By suggesting atoms are solid spheres

• By introducing a dense nucleus

• By placing electrons in fixed orbits or shells

Who discovered that the nucleus contains protons?

• James Chadwick

• Niels Bohr

• JJ Thompson

• Ernest Rutherford

What are protons and neutrons made of?

• Electrons

• Atoms

• Quarks

• Energy levels