Review of Law of Conservation of Mass

EXPERIMENT #1

REACTANT(S) ------> PRODUCT(S)

48.6g Magnesium + 32.0g Oxygen ------> 80.6g Magnesium Oxide.

Does this experimental data support the Law of Conservation of Mass?

• yes

• no

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

EXPERIMENT #3

REACTANT(S) ------> PRODUCT(S)

12 .2 g Magnesium + 8.0g Oxygen ------> _____Magnesium Oxide

Assuming that magnesium and oxygen will react completely with one another, predict the mass of magnesium oxide that will be produced. _________

• 12.2 g

• 8.0 g

• 20.2 g

• 4.2g

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

EXPERIMENT #4

If the cap had been removed during the reaction (open system), would there still be 44g of Product in the jar?

• No, some of the substance was lost out of the container as a gas

• Yes, mass can't be destroyed

Tags

NGSS.MS-PS1-5

A scientist mixed 100 grams of salt into a 500 grams of water. How many grams of salt water did I make?

• 500g

• 400g

• 600g

• 700g

A student heated a 10 gram sample of a compound in an open container. A chemical reaction occurred. The mass of the sample was measured again and found to be less than before. Which of the following explains the change in mass of the sample.

• The heat caused the compound to become less dense

• The reaction gave off more heat than was added

• Some of the lighter atoms were converted to energy

• One of the reaction products was a gas.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which of the following is a physical change?

• rusting metal

• boiling water

• leaves changing color

• bubbling of an antacid tablet in water

What type of reaction absorbs thermal energy?

• exothermic

• endothermic

Tags

NGSS.MS-PS1-6

If you heat a substance in a test tube and it starts as green and after heating is black, you have observed a ____________

• Chemical change

• Physical Change

• Psychological change

• Physical Property

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Is the equation balanced?

• yes

• no

Tags

NGSS.MS-PS1-5

Is the equation balanced?

• yes

• no

Tags

NGSS.MS-PS1-5