7th Grade Physical Science Chemical Reactions

What type of reaction is this?

2 C₆H₁₄ + 19 O₂ --> 12 CO₂ + 14 H₂O

• Single replacement

• Double replacement

• Combustion

• Decomposition

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The reactants are on the left side of the chemical equation.

• true

• false

Coal contains carbon and other elements. Carbon dioxide forms when coal burns in the presence of oxygen. Which of these is the best evidence that a chemical reaction occurs when coal burns?

• the shape of the coal changes

• oxygen is present

• a new substance is produced

• coal is made up of more than one element

Tags

NGSS.MS-PS1-2

Is burning wood a chemical or physical change?

• chemical

• physical

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What is this reaction?

K + HCl --> H₂ + KCl

• synthesis

• decomposition

• double replacement

• single replacement

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

In a complete chemical equation, there must be the same number of atoms of each element on the reactants and products side.

• true

• false

Tags

NGSS.MS-PS1-5

A new substance with unique chemical and physical properties that is formed when two or more elements are chemically bonded during a chemical reaction.

• product

• compound

• molecule

• atom

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A chemical reaction or process that absorbs heat from the surroundings.

• endothermic

• exothermic

Tags

NGSS.HS-PS1-4

What does the Law of Conservation of Mass state?

• Matter cannot be gained nor lost in a chemical reaction.

• Matter can only be lost in a chemical reaction.

• Matter can only be gained in a chemical reaction.

• Matter can be gained and lost in a chemical reaction.

Tags

NGSS.MS-PS1-5

What is the right part of a chemical equation called _____.

• reactants

• products

• yields

• equilibrium

Tags

NGSS.MS-PS1-5