Characteristics of Chemical Reactions

A process that leads to the transformation of one set of chemical substances to another

• Reactants

• Chemical reaction

• Atom

• Product

• Molecule

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The substances initially involved in a chemical reaction

• Reactants

• Chemical reaction

• Atom

• Product

• Molecule

Tags

NGSS.MS-PS1-5

The substance that is produced from a chemical reaction

• Reactants

• Chemical reaction

• Atom

• Product

• Molecule

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A __________ increase or decrease and the production of light are both signs that a chemical reaction may have occurred.

• temperature

• gas

• evidence

• odor

Tags

NGSS.MS-PS1-2

A _____________ is a solid substance that forms and separates from a solution and may indicate that a chemical reaction has occurred.

• molecules

• precipitate

• temperature

• gas

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Hydrogen and oxygen react to form water. At an atomic level, how do we know that a chemical reaction has occurred?

• The hydrogen and oxygen atoms regroup into a new molecule.

• Hydrogen molecules are negative, and oxygen positive.

• For every oxygen atom, two hydrogen atoms are needed.

• Oxygen atoms are much larger than hydrogen atoms.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which of the following is the best description of the results of a chemical reaction?

• A new substance with different properties is formed.

• The substance seems to disappear after dissolving in water.

• The substance changes from liquid to solid at a low temperature.

• The reaction can be reversed to get back the original substance.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Rust forming on a piece of iron is an example of which of the following:

• A physical change because the process can be reversed

• The natural process of decay as metallic ions age

• A chemical change because oxygen atoms from the atmosphere bonded with the iron atoms

• A violation of the laws of physics because new mass has been created

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which of the following statements is true?

• We know combining Substances A and B resulted in a chemical reaction because a gas was formed

• We know combining Substances C and D resulted in a chemical reaction because of the lack of a temperature change

• We know combining Substances A and B resulted in a chemical reaction because of the lack of a temperature change

• We know combining Substances A and B resulted in a chemical reaction because of the lack of a temperature change

Tags

NGSS.MS-PS1-2

Which of the following statements is true?

• Cutting paper is an example of a chemical reaction because a new substance is formed and the process cannot be undone

• Freezing water is an example of a chemical reaction because a new substance is formed and the process cannot be undone

• Melting ice is an example of a chemical reaction because a new substance is formed and the process cannot be undone

• Burning paper is an example of a chemical reaction because a new substance is formed and the process cannot be undone

Tags

NGSS.MS-PS1-2