Chemical Reactions

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-PS1-2

NGSS.MS-PS1-5

The number in front of a compound or element is a 

• Subscript
• Coefficient
• Superscript
• Charge

The number to the lower side of an element is a 

• Subscript
• Superscript
• Coefficient
• Charge

Matter can not be created nor destroyed: it can only be

• Destroyed a little bit
• Invisible
• Transformed, changed
• None of the above

Tags

NGSS.MS-PS1-5

If a reaction starts with a total 75g of reactants it should produce 

• a total of 40g of products
• a total of 75g of products
• a total of 180 g of products
• None of the above

Tags

NGSS.MS-PS1-5

Fill in the blanks with coefficient:
PCl₅+_ H₂O→_ HCl+H₃PO₄

• 4, 5
• 1, 6
• 3, 8
• 2,2

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which side of a chemical equation is the product side?

• Left (before the yields sign)
• Right (after the yields sign)

Which problem is balanced?

• PbO₂ + 2H₂--> H₂SO₄
• SO₂ + H₂0 --> H₂SO₄
• 2Na + 2H₂O --> 2NaOH + H₂
• 2Na + 2H₂O --> 2NaOH + H

Tags

NGSS.MS-PS1-5

Balance this equation
_Zn+_HCl-->_ZnCl₂ +_H₂

• 1,1,2,1
• 1,1,1,2
• 1,2,1,1
• 2,1,1,1

Tags

NGSS.MS-PS1-5

2 NaBr + 1 Ca(OH)₂ ----> 1 CaBr₂ + 2 NaOH

• Synthesis (or combination)
• Decomposition
• Single displacement
• Double displacement

Tags

NGSS.MS-PS1-5