Conservation of Mass Quiz

In an open system, what happens to the mass during a chemical change?

• The mass remains constant.

• The mass decreases.

• The mass increases.

• The mass change depends on if particles can enter or exit the system.

Tags

NGSS.MS-PS1-5

In a closed system, what happens to the mass during a chemical change?

• The mass increases.

• The mass decreases.

• The mass remains constant.

• The mass changes depending on if particles can enter or exit the system.

Tags

NGSS.MS-PS1-5

In an open system, what happens to the mass during a physical change?

• The mass increases.

• The mass remains constant.

• The mass decreases.

• The mass change depends on if particles can enter or exit the system.

Tags

NGSS.MS-PS1-2

Give an example of an open system in a physical change.

• Boiling pot of water

• Melting ice cube

• Burning candle

• Rusting iron

Tags

NGSS.MS-PS1-4

Give an example of a closed system in a physical change.

• Open container containing gas

• Unsealed bottle containing gas

• Sealed bottle containing gas

A piece of copper metal is mixed with aqueous silver nitrate as shown below. What happens to the mass?

Cu + AgNO3 --> Ag + CuNO3

• The mass stays the same because the change is chemical

• The mass stays the same because the mass is physical

• The mass stays the same because no particles would enter or exit the system.

• The mass increases because silver weighs more than copper.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Iodine sublimates (goes from a solid to a gas) in a sealed flask according to the equation below. Which of the following is true?

I_{2 (s)} --> I_{2 (g)}

• The mass decreases because gases weigh less than solids.

• The mass stays the same because it is a physical change.

• The mass increases because gases weigh more than solids.

• The mass stays the same because the system is closed.

Tags

NGSS.MS-PS1-4

Zinc reacts with hydrochloric acid in a beaker according to the reaction below... Which of the following is true?

Zn + 2HCl --> ZnCl2 + H₂

• The mass decreases because hydrogen gas weighs less than HCl

• The mass stays the same because it is a chemical change.

• The mass increases because it is a chemical change.

• The mass decreases because a gas is produced in an open system.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Magnesium burns with oxygen in a bunsen burner according to the reaction below- which of the following is true?

2Mg + O₂ --> 2MgO

• The mass increases because fire adds particles to the Mg

• The mass increases because oxygen is added to the Mg

• The mass increases because it is a chemical change.

• The mass decreases because it burns and burning things always decreases mass.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Methane gas is burned in an open container according to the reaction below. Which of the following is true?

CH₄ + O₂ --> CO₂ + H₂O

• The mass increases because burning things always increases the mass.

• The mass decreases because the products are all gaseous.

• The mass stays the same because it is an open system.

• The mass decreases because burning things always reduces the mass.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2