The Atom Review

Which electron configuration represents the electrons of an atom in an excited state?

• 2-8-2

• 2-7-3

• 2-8-9-2

• 2-8-8-1

Tags

NGSS.HS-PS1-1

Which conclusion was proposed as a result of an experiment during which some alpha particles were deflected while passing through a thin sheet of gold foil?

• Atoms have small, dense, positive nuclei

• Atoms are hard, indivisible spheres

• Atoms have electrons with wavelike properties

• Atoms contain negatively charged particles.

In the ground state, which shell of a potassium atom has an electron with the greatest amount of energy?

• third

• fourth

• first

• second

Tags

NGSS.HS-PS1-1

The mass of each proton and each neutron is approximately equal to

• 1 mol

• 1 mL

• 1 u

• 1 g

What is the number of protons in an atom with the electron configuration of 2–5?

• 3

• 7

• 5

• 2

Tags

NGSS.HS-PS1-1

According to the electron cloud model, which term is defined as the most probable location of an electron in an atom?

• nucleus

• spectrum

• orbital

• configuration

An element is composed of atoms that must have

• a different number of protons

• the same atomic number

• the same atomic mass

• a different number of electrons

A potassium atom has a mass number of 37. What is the number of neutrons in this atom?

• 15

• 37

• 18

• 22

The numbers of protons, neutrons, and electrons in each of four different ions are shown in the table below. Which ion has the greatest mass?

• G

• E

• A

• Z

Which phrase describes a specific compound?

• can be physically separated into elements

• is composed of elements chemically combined in a definite ratio

• can contain only one element

• is composed of elements mixed in proportions that can vary