Properties of Atoms and the Periodic Table

The symbol for chlorine is ____________.

• Ci

• Cl

• Ch

• Cr

The sum of the number of protons and the number of neutrons in an atom is the ___________________________.

• atomic number

• atomic mass

• isotopes

• mass number

The central core of an atom is called the _____________.

• nucleus

• neutron

• proton

• electron

The atomic masses of the elements are not whole value numbers because of the existence of __________________________.

• protons

• isotopes

• neutrons

• electrons

Two isotopes of carbon are carbon-12 and carbon-14. These isotopes differ from one another by two _____________.

• protons

• electrons

• neutrons

• isotopes

Tags

NGSS.HS-PS1-8

The mass of a _________________ is about equal to the mass of a proton.

• proton

• neutron

• electron

• isotope

Quarks can be produced by bombarding ________________________ with protons.

• electrons

• neutrons

• protons

• isotope

The chart showing the classifications of elements according to their properties and increasing atomic numbers is called the __________________________.

• period table

• table of periodic

• periodic table

• table of period

_______________________ are poor conductors of heat and electricity.

• Metals

• Nonmetals

• Metalloid

• Recently discovered

The region around the nucleus occupied by the electrons is called the ________________________________.

• proton cloud

• neutron cloud

• electron cloud

• nucleus cloud