Chemical Reactions

One reactant with a mass of 4 grams, is combined with another reactant, with a mass of 12 grams, in a sealed container. After the reaction, what is the most reasonable prediction for the total mass of the products of this reaction?

• 3g

• 4g

• 12g

• 16g

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Which of the following is true regarding the atoms involved in a chemical reaction?

• The same number of each type of atom will always be present before and after a chemical reaction takes place.

• Some of the atoms present before the reaction will always be lost during a chemical reaction.

• Some of the atoms will always be changed into a different type of atom by a chemical reaction.

• During a chemical reaction, atoms will always be combined into much larger molecules.

Tags

NGSS.MS-PS1-5

The mass of all the reactants must equal the mass of all the products. Matter is neither created nor destroyed.

• chemical reaction

• chemical formula

• law of conservation of mass

• product

Tags

NGSS.MS-PS1-5

The process by which one or more substances change to produce one or more different substances is

• chemical reaction

• reactant

• subscript

• coefficient

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

What is the number that tells you how many atoms of an element there are in a chemical formula?

• coefficient

• subscript

• law of conservation of mass

• product

What tells you how many molecules are present?

• reactant

• product

• subscript

• coefficient

Subscripts for a particular kind of molecule never change because these numbers describe how many of an atom type are present in a particular molecule.

• True

• False

Tags

NGSS.MS-PS1-1

What happens when chemical bonds break and new bonds form?

• a physical change
• a chemical reaction
• matter is destroyed
• surface area increases
  

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

What are the products of the chemical reaction pictured?

• CH₄ and CO₂

• CH₄ and O₂

• CO₂ and H₂O

• O₂ and H₂O

Tags

NGSS.MS-PS1-2

Identify the reactant(s) and product(s) of the reaction.

• All three are reactants and none are products.
• Hydrogen and water are the reactants, and oxygen is the product.
• Water and oxygen are the reactants, and hydrogen is the product.
• Hydrogen and oxygen are the reactants, and water is the product.