Atomic Structure

The number of neutrons in the nucleus of an atom can be calculated by

• adding together the numbers of electrons and protons.

• subtracting the number of protons from the number of electrons.

• subtracting the number of protons from the mass number.

• adding the mass number to the number of protons.

The sum of the protons and neutrons in an atom equals the

• atomic number.

• number of electrons.

• atomic mass.

• mass number.

All atoms of the same element have the same:

• number of protons.

• number of neutrons

• mass number

• mass

Tags

NGSS.MS-PS1-1

An atom of an element with atomic number 48 and mass number 120 contains

• 48 protons, 48 electrons, and 72 neutrons.

• 72 protons, 48 electrons, and 48 neutrons.

• 120 protons, 48 electrons, and 72 neutrons.

• 72 protons, 72 electrons, and 48 neutrons.

Tags

NGSS.MS-PS1-1

How do the isotopes hydrogen-2 and hydrogen-3 differ?

• Hydrogen-3 has one more electron than hydrogen-2.

• Hydrogen-3 has two neutrons.

• Hydrogen-2 has three protons.

• Hydrogen-2 has no protons.

Tags

NGSS.MS-PS1-1

The number 80 in the name bromine-80 represents

• the atomic number.

• the mass number.

• the sum of protons and electrons.

• none of the above

The identity of an element can be determined on the basis of which of the following?

• the number of protons in an atom of the element

• the number of neutrons in an atom of the element

• the mass number of the element

• the atomic mass of the element

Tags

NGSS.MS-PS1-1

An atom of hydrogen-2 contains

• 2 protons, 2 electrons, and 2 neutrons.

• 2 protons, 2 electrons, and 4 neutrons.

• 1 proton, 1 electron, and 1 neutron.

• 1 proton, 1 electron, and 2 neutrons.

Tags

NGSS.MS-PS1-1

Which of the following statements is correct?

• Each vertical column of elements in the periodic table is called a period.

• The elements in any group or vertical column of the periodic table have similar physical and chemical properties.

• Group 1A contains the elements hydrogen and helium.

• In the modern periodic table, elements are listed in order of increasing atomic mass.

Isotopes of the same element have

• the same number of protons but different numbers of neutrons.

• the same number of protons but different numbers of electrons.

• the same number of neutrons but different numbers of protons.

• the same number of neutrons but different numbers of electrons.

Tags

NGSS.HS-PS1-8