the center of the atom is called the _________________.

• protons

• neutrons

• nucleus

• atomic center

• tech center

Anything that has mass and takes up space is called ________.

• density

• volume

• matter

• atoms

The amount of space an object takes up is called ________.

• volume

• matter

• mass

• density

Most of the mass of an atom is found in the ____________.

• protons

• quarks

• nucleus

• electron cloud

No two elements have the same _______________.

• number of neutrons

• number of protons

• color

• atomic mass

homogeneous means

• the same throughout

• different throughout

• a mixture

• a compound

milk is a

• mixture

• element

• compound

two or more substances not chemically combined

• element

• mixture

• compound

a pure substance containing two or more types of atoms that are chemically combined.

• element

• compound

• mixture

water

• element

• compound

• mixture