Unit 3 Review

Ancient atomic models described the atom as a solid sphere with no charge. In the 1800's and 1900's, scientist discovered subatomic particles with charges inside the atoms.

Which statement most likely explains why the early models did not include the subatomic particles?

• atoms changed over time to develop the subatomic particles

• not all atoms contain subatomic particles

• subatomic particles move and cannot be counted

• subatomic particles could not be detected with the technology available.

Which statement correctly describes the mass of a proton?

• the mass of a proton is about the same as the mass of a neutron

• the mass of proton is about the same as the mass of an electron

• the mass of a proton is about double the mass of a neutron

• the mass of a proton is about half the mass of an electron.

A student makes an atomic model, as shown. How should the atomic model be corrected to represent an atom accurately?

• electrons should not have any charges

• neutron should not reside inside the nucleus

• the nucleus should be located at the center of an atom

• Protons and neutron should both have positive charges

Tags

NGSS.MS-PS1-1

The image show an incomplete model of an atom. Which particles should be placed inside the nucleus?

• protons only

• electrons only

• electrons and protons

• neutrons and protons

Tags

NGSS.MS-PS1-1

Using the periodic table as a reference, which pair of elements are nonmetals.

• oxygen and sulfur

• cobalt and zinc

• mercury and lead

• sodium and iodine

What is the significance of a column in the periodic table?

• a column, better know as a group includes elements with similar

• a column, better know as a period, includes elements with similar properties

• a column, better known as a group, includes elements with the same number of electrons

• a column, better known as a period, include elements with the same number of electrons.

How are elements organized into the periodic table?

• elements are ordered by atomic weight

• elements are ordered by atomic number

• elements are arranged alphabetically

• elements are grouped by color

What type of bond is frequently formed from reactions between metals and nonmetals?

• covalent bonds

• hydrogen bonds

• ionic bonds

• metallic bonds

Tags

NGSS.HS-PS1-1

Referring to the reference periodic table, what do the elements fluorine, chlorine, and bromine have in common?

• all are located in the same period

• all have metallic properties

• all are halogens, so they are not very chemically active

• all have the same number of valence electrons

What information can be used to infer an element's chemical reactivity?

• physical properties of matter

• states of matter

• columns of the periodic table

• row on the periodic table