Atomic Structure Worksheet

Which subatomic particle has a positive charge?

• Electron

• Neutron

• Proton

• Photon

Rutherford's gold foil experiment led to which discovery?

• The electron

• The neutron

• The existence of a small, dense, positively charged nucleus

• That atoms were mostly solid spheres

The atomic number of an element is defined as the number of:

• Neutrons

• Protons

• Protons and neutrons

• Protons, neutrons, and electrons

How are two isotopes of the same element different from each other?

• They have a different number of protons.

• They have a different number of electrons.

• They have a different number of neutrons.

• They have a different atomic number.

The 'plum pudding' model of the atom was proposed by which scientist?

• Niels Bohr

• J.J. Thomson

• Ernest Rutherford

• John Dalton

Which of the following describes an ion?

• An atom with a different number of neutrons than protons.

• An atom with a different number of electrons than protons.

• An atom that is electrically neutral.

• An atom that is radioactive.

An atom contains 11 protons, 12 neutrons, and 11 electrons. What is its mass number?

• 11

• 12

• 23

• 34

What is the approximate mass of a proton in atomic mass units (amu)?

• 0 amu

• 1 amu

• 1/1840 amu

• 2 amu

The modern model of the atom describes the location of electrons as:

• Fixed orbits around the nucleus.

• Within the nucleus.

• In a region of space with a high probability of finding an electron, called an orbital.

• Randomly distributed throughout the atom.

According to the law of definite proportions, a given chemical compound always contains the same elements in the exact same proportions by:

• Volume

• Mass

• Moles

• Density