Chemistry Review

Which pair of elements has the most similar properties?

• Li and B
• I and Ca
• K and He
• N and P

Which statement best explains how periods on the periodic table are organized?

• increasing atomic number from left to right
• increasing number of neutrons from left to right
• decreasing number of electrons from left to right
• decreasing atomic mass number from left to right

Where are the most reactive metals located on the periodic table?

• the uppermost complete row of the table
• the rows at the bottom of the table connecting two section
• the column at the far left side of the table
• the second column from the right side of the table

If an element has no electrons to share and is stable, what family is it found in?

• alkali metals
• noble gases
• halogens

Why are certain elements placed into the same column on the periodic table?

• They have the same number of protons in their nuclei.
• They have the same number of electrons in their nuclei.
• They have the same number of electrons in their outer energy level.

Which best describes a row of elements in the periodic table?

• column
• family
• group
• period

If a chemical reaction such as photosynthesis begins with 6 atoms of carbon (C), how many atoms of carbon (C) should be in the products?

• 12 atoms of carbon (C)
• 6 atoms of carbon (C)
• 3 atoms of carbon (C)
• 2 atoms of carbon (C)

Which best explains why the total mass of the product(s) would be less than the total weight of the reactant(s) after a chemical reaction?

• A physical change occurred.
• Atoms involved in the reaction lost mass.
• Precipitates were created in the new solution.
• Gases were released to the atmosphere.

What coefficient for O₂ demonstrates the law of conservation of mass?
CH₄(g) + __O₂(g) → CO₂(g) + 2H₂O(g)

• 1
• 2
• 3
• 4

____ are building blocks of matter

• atoms
• protons
• things
• molecules