Science1

The atomic number of an atom is equal to the number of (protons, neutrons) in its nucleus.

protons

The nucleus of an atom is made up of neutrons and (electrons, protons).

protons

How many periods in the periodic table?

7

How many elements are naturally occurring?

88

The building blocks of matter are (atoms, compounds).

atoms

Protons are particles (outside, in) the nucleus of an atom.

in

Carbon-14 is an (isotope, element) of carbon.

isotope

Two atoms of the same element that have different (mass number, atomic numbers) are isotopes of the element?

mass numbers

Anything that takes up space and has mass in (matter, an element).

matter

Two types of properties the elements in the periodic table have?

metals; non-metals

Electrons are atomic particles with a (positive, negative) charge.

negative

(Neutrons, protons) are particles in the atom's nucleus that have no electric charge.

neutrons

Isotopes are atoms of the same element that have different numbers of (neutrons, protons).

neutrons

In atoms with equal numbers of electrons and protons, there is (a positive, no) electric charge.

no

The nucleus of an atom has a (positive, negative) charge.

positive

How many families are there in the periodic table?

18

Where are the noble gases located?

18 family

Who developed the first periodic table?

Dimitri Mendalaya

An example of matter is (air, heat).

air

A difference in the (mass number, atomic number) of atoms means the atoms are of different elements.

atomic number

What do noble gases have in common?

colorless; odorless; not radioactive

Negatively charged particles that move around the atom's nucleus are (neutrons, electrons)

electrons

The atomic particles outside of the atom's nucleus are are (electrons, protons).

electrons

Substances made up of only one kind of atom are called (isotopes, elements).

elements

What ultimately determines an elements position in the periodic table?

energy levels

Where are the alkali metals?

family 1