Chemical Bonds, Reactions, Equations

What happens in a chemical reaction?

• Bonds between atoms break and/or are formed

• New atoms are created and/or removed

• Protons move from one atom to another

• Electrons change into protons

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5

NGSS.MS-PS1-2

How are chemical bonds formed?

• Atoms duplicate themselves

• Electrons move from one atom to another

• The number of protons and electrons in an element is changed

• Through changes in an atom's nucleus

Tags

NGSS.MS-PS1-1

Which of the following would indicate that a chemical reaction has occurred?

• A new element has been created

• A different substance has formed

• The total mass has either increased OR decreased

• The total number of elements has either increased OR decreased

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

How many sulfur atoms are present in this molecule?

• 4

• 3

• 12

• 1

Tags

NGSS.MS-PS1-1

In the molecule below, which of the following choices is a subscript? (Select all that apply)

• 3

• 2

• 4

• SO

Tags

NGSS.MS-PS1-1

What does the Law of Conservation of Mass state?

• No new substances can be made or destroyed

• No new compounds can be made or destroyed

• No new atoms can be made or destroyed

• Mass cannot be lost from a physical reaction

Tags

NGSS.MS-PS1-5

In a chemical reaction, ________________________ are changed into _______________________.

• Reactants; Products

• Electrons; Molecules/Compounds

• Coefficients; Subscripts

• Original Elements; New Elements

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Bacteria in milk causes it to curdle over time. What type of change is this?

• Chemical

• Physical

• Both

• Neither

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

How many atoms of carbon (C) are in  C₆H₁₂O₆?

• 3
• 6
• 12
• 24

Tags

NGSS.MS-PS1-1

Element or compound?
H₂O

• element
• compound

Tags

NGSS.MS-PS1-1