Unit 8 Physical Science Test Review

Who was the scientist that created the first periodic table?

• Dmitri Mendeleev
• Albert Einstein
• Niels Bohr
• John Dalton

Answer explanation

Dmitri Mendeleev is known for creating the first periodic table, which organized elements by increasing atomic mass.

How is the modern periodic table primarily arranged?

• By atomic mass
• By atomic number
• Random order
• By alphabetical order

Answer explanation

The modern periodic table is arranged by atomic number, which is the number of protons in an atom's nucleus.

What do we call the vertical columns in the periodic table?

• Groups
• Periods
• Rows
• Sections

Answer explanation

The vertical columns are called groups, which contain elements with similar chemical properties.

What do we refer to the horizontal rows of the periodic table as?

• Groups
• Periods
• Columns
• Layers

Answer explanation

The horizontal rows are known as periods, which indicate the energy levels of the elements' electrons.

Which of the following elements are considered metals?

• Oxygen
• Iron
• Helium
• Carbon

Answer explanation

Iron is a metal, while oxygen, helium, and carbon are nonmetals.

Elements located to the left of the periodic table are typically classified as what?

• Nonmetals
• Metalloids
• Metals
• Gases

Answer explanation

Elements to the left are classified as metals, which are generally good conductors of heat and electricity.

Which element stands out as unique among the following?

• Calcium
• Helium
• Francium
• Magnesium

Answer explanation

Helium is a noble gas and is unique because it is a nonmetal and highly unreactive compared to the other metals listed.

What group does fluorine belong to?

• Group 1
• Group 2
• Group 17
• Group 18

Answer explanation

Fluorine belongs to Group 17, which is known as the halogens.

How many valence electrons does boron have?

• 3.0
• 4.0
• 1.0
• 5.0

Answer explanation

Boron has 3 valence electrons, which are found in the outermost shell of its atom.

In which period is magnesium located?

• Period 2
• Period 3
• Period 4
• Period 5

Answer explanation

Magnesium is located in Period 3 of the periodic table.