Cbq 4 Review

Which is Chemical Equation is Balanced?

• CH₄+O₂------CO₂+2H₂O
• H₂+O₂-----2H₂O₄
• 4Al+3O₂-----2Al₂O₃

Tags

NGSS.MS-PS1-5

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

When balancing equations a ____ can be placed to the left of a formula of a substance to make the equations balanced

• charge
• subscript
• random number
• coefficient

In this image, what are the information in red is called the_______.

• Product
• Reactant
• Chemical Subscript

Tags

NGSS.MS-PS1-1

In this image, what are the information to the right of the arrow (in black) is called the_______.

• Product
• Reactant
• Chemical Subscript

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

Is this balanced?...
Al + O₂ --> 2Al₂O₃

• Yes!
• NO!

Tags

NGSS.MS-PS1-5

What is the little number after an element in a chemical equation called.
Example: H₂

• Coefficient 
• Subscript
• Atom
• Equation

Balance this equation-
__P₄ + __O₂ --> __P₂O₃

• it is already balanced
• 2, 1, 3
• 1, 2, 3
• 1, 3, 2

Tags

NGSS.MS-PS1-5

What is the coefficient of the oxygen molecule (O₂) in the elephant toothpaste equation?

2 H₂O₂ -> 2 H₂O + O₂

• 0

• 1

• 2

• 4

Calculate the mass of  5 mol of iron atoms.

• 5
• 56
• 130
• 280

Tags

NGSS.HS-PS1-7