Atomic Structure

John Dalton modeled the atom as a...

• tiny solid sphere, with a known mass
• a hollow sphere
• a marble in the middle of a stadium
• planets orbiting around a star

J.J. Thomson provided evidence that an atom...

• is the smallest particle of matter
• contains negatively charged particles
• has an overall negative charge
• has an overall positive charge

Tags

NGSS.HS-PS1-3

Rutherford's gold foil experiment provided evidence that...

• negative and positive charges are spread evenly throughout the atom.
• alpha particles have a positive charge.
• gold is not a dense as previously thought.
• there is a dense positively charged nucleus at the center of an atom.

Tags

NGSS.HS-PS1-8

Rutherford's model of an atom most closly resenbles...

• an avocado with the pit being the nucleus..
• an aquarium with fish swimming around to represent the positive charges.
• a fried egg with the yoke representing the nucleus.
• a stadium with a marble in the middle representing the nucleus.

Tags

NGSS.HS-PS1-8

Which statement about subatomic particles is true?

• Protons, neutrons, and electrons all have about the same mass.
• Unlike protons or neutrons, electrons have no mass.
• Neutrons have no charge and no mass.
• An electron has far less mass than either a proton or neutron.

Which of the following is unique for any given element?

• the number of neutrons
• the charge on the electrons
• the number of protons
• the mass of a neutron

Which statement is true about oxygen-17 and oxygen-18?

• They do not have the same number of protons.
• Their atoms have an identical mass.
• They are isotopes of oxygen.
• The have the same mass number.

The glowing of a neon light is caused by electrons emitting energy as they

• move from lower to higher energy levels.
• collide with other electrons.
• move from higher to lower energy levels.
• collide with the nucleus.

The atomic mass of a single atom  is

• the sum of the protons and neutrons in the atom.
• twice the number of protons in one atom of the element.
• a ratio based on the mass of a carbon-12 atom.
• a weighted average of the masses of the element’s isotopes.

An atom with an unequal number of protons and electrons is said to have (a) ___.

• no charge
• balance
• charge
• unbalance