Periodic Table, Chemical Bonds, and Chemical Reactions

Mendeleev arranged the elements by

• color

• the number of neutrons

• increasing atomic number

• increasing atomic mass

Why don't noble gases normally form chemical bonds?

• They have 2 valence electrons.

• They have a full outermost energy level.

• They have an empty outer level.

• They have 8 protons.

Most metals are solid at room temperature except for ________________ which is a liquid.

• bromine

• aluminum

• mercury

• carbon

Elements whose atoms are radioactive are found in the

• halogen group.

• actinide group.

• lanthanide group.

• alkali metal group

Tags

NGSS.HS-PS1-8

What is the joining of atoms to form new substances?

• chemical bonding

• solution

• joining chemicals

• mixture

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Periodic law states that

• elements are either gases, solids, or liquids.

• mercury is a liquid at room temerature.

• properties of elements repeat periodically with the elements' atomic numbers

• some elements only stay in a liquid state for short periods.

What is the source of activation energy that ignites a strike-anywhere match?

• sunlight

• friction

• motion

• heat

The solid substance that forms as a result of a chemical reaction in solution is ___________________.

• a colloid

• a precipitate

• a solute

• a suspension

Tags

NGSS.MS-PS1-2

Photosynthesis (6CO₂ + 6H₂0 + light energy →C₆H₁₂O₆ + 6O₂) is an example of ___________________.

• an exothermic reaction

• respiration

• an endothermic reaction

• releasing energy

Tags

NGSS.MS-LS1-6

NGSS.MS-LS1-7

What can group numbers on the periodic table help you determine?

• the number of valence electrons

• the number of electrons

• the number of protons

• the number of neutrons