Atomic Structure

Which of the following groups of subatomic particles are comparable in size and mass?

proton and neutron

what is all matter made of?

atoms

the radius of an atom is closest in size to a ______.

nanometer

The ______ is a small, dense, positively-charged region at the center of the atom.

nucleus

What do all atoms of the same element have in common?

number of protons

Overall, the nucleus of an atom has a(n) _____ charge.

positive

Which of the following are features of the nucleus of an atom?

-The nucleus has a tiny size relative to the total space occupied by the atom. -The nucleus is located at the center of the atom. -It has relatively great mass compared to the other components of the atom. -The nucleus contains protons and neutrons.

Subatomic particles that do not possess any charge but provide mass to atoms are called _____.

Neutrons

what is contained in the nucleus of an atom?

Protons and neutrons

Where are the subatomic particles located?

The protons and neutrons are found inside the nucleus, and the electrons are found on the valence shells

An _____ is the smallest particle of an element that has the element's properties.

atom

the density of nuclear matter:

does not change with the atomic numbers

Which of the following subatomic particles orbits the nucleus?

electron

which of the following are not located in the nucleus of an atom

electron

Particles that "orbit" the center of an atom are called

electrons

Atoms of helium or nickel would represent _____. These are pure substances that can not be broken down into simpler materials or particles.

elements

Because protons and neutrons make up the nucleus, and protons have a positive charge, neutrons have a negative charge.

false

Electrons are significantly smaller than protons and neutrons, we can ignore electrons when we consider the physical property of an atom.

false

Only a million atoms would fit inside the period at the end of this sentence.

false

The strong nuclear force holds together the electrons and the neutrons while electrical charges push the electrons away from each other.

false

There is an electric force of repulsion between neutrons and protons.

false

the nucleus makes up about 1/100th of the total radius of an atom

false

the nucleus of all atoms must consist of protons and neutrons

false

the small, dense region at the center of an atom is the _____.

nucleus

A neutral atom has equal numbers of ____ and electrons.

protons

Subatomic particles with a positive charge are known as _____.

protons

Which describes the density of the atomic nucleus compared to the density of the entire atom?

the density of the nucleus is very much larger than that of the atom

All atoms of the same element have the same number of protons.

true

An atom containing an equal number of protons and electrons is electrically neutral.

true

In a neutral atom, the number of protons is equal to the number of electrons.

true

The nucleus is very dense because it has virtually all of the atom's mass, but just a tiny fraction of the atom's total size.

true

The nucleus of an atom consists of protons and neutrons bound by a strong nuclear force.

true

the nucleus of the atom is a positively charged region at the center of an atom, which consists of protons and neutrons

true

there is an electrical force of repulsion between protons in the nucleus

true