Chemical Bonding and Reactions

What does a chemical bond join together into a molecule?

• electrons

• atoms

• nuclei

• elements

Tags

NGSS.MS-PS1-1

In the Bohr Model, where are the valence electrons shown?

• nucleus

• innermost energy level

• outermost energy level

• in the electron cloud

In Group 16 of the Periodic Table of the Elements, how many valence electrons does each element have?

• 0

• 7

• 16

• 6

How many valence electrons do nitrogen atoms have?

• 2

• 5

• 7

Tags

NGSS.MS-PS1-1

Helium (He) has two valence electrons in its first and only energy level. Why is helium nonreactive and tends not to form bonds?

• The outermost energy level is full

• Helium does not have enough electrons to share

• The atomic number and atomic mass are too small

• Helium only reacts with hydrogen to form helium hydroxide

Tags

NGSS.MS-PS1-1

What is a reactant?

• a precipitate from a chemical reaction

• an enzyme

• a substance that participates in a chemical reaction

• a substance that is produced in a chemical reaction

Tags

NGSS.MS-PS1-2

What is the name for the process in which atoms are rearranged to produce new substances?

• conservation of mass

• catalytic conversion

• chemical bond

• chemical reaction

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

In the image, what is the number 2?

• coefficient

• ion

• subscript

• product

Tags

NGSS.MS-PS1-1

What do you change to balance a chemical equation?

• coefficients

• subscripts

• catalysts

• valence electrons

Tags

NGSS.MS-PS1-5

A balanced chemical equation shows that chemical reactions follow which law?

• law of endothermic and exothermic reactions

• law of conservation of energy

• law of conservation of resources

• law of conservation of mass

Tags

NGSS.MS-PS1-5