Chemical Equations

The mass of the reactants in a chemical equation is 100 grams. There are two products. One products mass is 65 grams. What is the mass of the other product?

• 45 grams

• 100 grams

• 35 grams

• 65 grams

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Using the equation below answer the following question. How many O's are on each side of the equation?

4 Fe + 3 O₂     → 2 Fe₂O₃

• 2

• 3

• 6

• 1

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

NGSS.MS-PS1-1

According to the law of conservation of mass,

• A new kind of matter is created.

• Matter is destroyed.

• Matter is not created or destroyed.

• New matter is created and changes form.

Tags

NGSS.MS-PS1-5

According to the law of conservation of mass,

• Mass increases or decreases

• the same amount of mass remains.

• Amount of mass may change after the reaction.

• Mass of the reactants and products will almost be equal.

Tags

NGSS.MS-PS1-5

When a bicycle rusts, rust is a

• reactant

• product

• physical change

• catalyst

Tags

NGSS.MS-PS1-5

The reactants in a chemical equation weigh 50 grams. There are 2 products. One product weighs 15 grams. The other product must weigh _______.

• 50 grams

• 15 grams

• 25 grams

• 35 grams

Tags

NGSS.MS-PS1-5

You mix baking soda and vinegar in a beaker. The weight of the product is less than the weight of the reactants. Which of the following accounts for the difference in weight?

• One product was a gas that escaped into the surrounding air.

• The reaction created a precipitate that formed in the bottom of the beaker.

• Heat was given off.

• Some matter was destroyed.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

When a fire occurs, which of the following is true?

• Matter is destroyed.

• Matter is created.

• Matter changes form into ash, water vapor, and carbon dioxide fumes.

• Matter does not change form.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

NGSS.MS-PS1-4

Due to the law of conservation of matter a chemical equation must have

• only the same elements on both sides. The number of atoms does not matter.

• The same elements on both side and the same number of atoms.

• only the same number of atoms. The number of elements does not matter.

Tags

NGSS.MS-PS1-5

In Elephant toothpaste we broke hydrogen peroxide down into water and oxygen. Which of the following formulas demonstrate the law of conservation of mass?

• H₂O₂ → H₂O + O₂

• 2 H₂O₂ → 2 H₂O + O₂

• 2 H₂O₂ → H₂O + O₂

• H₂O₂ → 2 H₂O + O₂

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2