Conservation of Mass Follow up

How many oxygen atoms are in this chemical formula?

• 6 oxygen atoms

• 2 oxygen atoms

• 3 oxygen atoms

• 4 oxygen atoms

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NGSS.MS-PS1-1

What is the Law of Conservation of mass?

• Mass is created in a chemical reaction
• Mass is created in a physical change
• New chemicals formed from a chemical reaction have a larger overall mass than the original reactants
• Mass is never created or destroyed

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Which are the reactants in the following reaction?
2Mg + O₂ ---> 2MgO 

• Mg and O
• MgO
• Mg and MgO
• O and MgO

Tags

NGSS.MS-PS1-2

If you have 15 grams of Baking Soda and 20 grams of Vinegar as products, what would you expect the mass of your reactants to be?

• 15 grams

• 20 grams

• 5 grams

• 35 grams

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

In a chemical reaction, the mass of the reactants was 15g.  The mass of the products was 12g.  Did this chemical reaction follow the law of conservation of mass?

• Yes 
• No
• You can't tell with the given infomation 

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

There are two reactants in a chemical equation, and one product.  The mass of the product is 30g.  The mass of the first reactant is 17g.  What must the mass of the second reactant be, if the equation is to follow the law of conservation of mass?

• 47g
• 13g
• 23g 
• You cant tell with the given information

Tags

NGSS.MS-PS1-5

The principle of conservation of mass is true for

• Only reactions in an open system
• Only reactions in a closed system
• For reactions in both an open and closed system
• No reactions

Tags

NGSS.MS-PS1-5

Maria fills a bowl with 200 g of water. She puts the bowl of water in the freezer, and the water freezes. Which will most likely be the mass of the frozen water?

• 50 g
• 100 g
• 200 g
• 400 g

Tags

NGSS.MS-PS1-4

A 500-gram block of solid cheese is melted in a pot. Which is most likely the mass of the cheese after it is melted?

• 500 grams, because the cheese does not gain or lose mass just because it was melted
• 499 grams, because some of the cheese evaporates as it melts
• 502 grams, because the cheese absorbs heat as it melts

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-4

Jason poured 500 grams of water into a container and tightly sealed it. The water was allowed to freeze. Which is most likely true about the ice that formed?

• The mass of the ice is the same as the mass of the water.
• The mass of the ice is greater than the mass of the water.
• The ice formed is a different substance than the water.
• The ice formed is the same temperature as the water.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-4