Counting Molecules and Balancing Equation Retest

How many O's are in Al₂(SO₄)₃

• 4
• 12
• 7
• 24

Tags

NGSS.MS-PS1-1

Number of N in (NH₄)₂CrO₄

• 1
• 2
• 8
• 16

Tags

NGSS.MS-PS1-1

The law of conservation of matter states that

• chemical reactions change matter.
• in chemical reactions, the identity of reactants and products is conserved.
• atoms are neither created nor destroyed in chemical reactions.
• a chemical equation must be balanced.

Tags

NGSS.MS-PS1-5

Which of the following is an unbalanced equation?

• CaCO₃ --> CaO + CO₂

• PbO₂ + 2H₂-->2Pb + H₂O

• 2Na+ 2H₂O-->2NaOH + H₂

• CS₂ + 3O₂ --> CO₂ + 2SO₂

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

How many total atoms are in the compound C₂H₈O ?

• 11
• 2
• 8
• 1

Tags

NGSS.MS-PS1-1

Balance this equation

_Al +_HCl --> _H₂ +_AlCl₃

• 2,6,3,2

• it's already balanced

• 4,12,3,4

• 2,1,4,5

Tags

NGSS.MS-PS1-5

Is the equation balanced?: 2H₂O + O₂ --> 4MgO + 3Fe

• yes

• no

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Which of the following equations are correctly balanced?

• 12CO₂ +H₂O --> C₆H₁₂O₆ + O₂
• CO₂ + 9H₂O --> C₆H₁₂O₆ + O₂
• CO₂ + H₂O --> 3C₆H₁₂O₆ + O₂
• 6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6O₂

Tags

NGSS.MS-PS1-5

Balance the following equation:

___ Mg+ ___ O₂→___ MgO

• 1, 1, 3

• 2, 1, 2

• 1, 2, 1

• 2, 2, 2

Tags

NGSS.MS-PS1-5

Balance the following equation:

___ SeCl₆+ ___ O₂→___ SeO_{2+____}Cl₂

• 1, 1, 1, 3

• 2, 1, 2, 1

• 1, 2, 1, 2

• 2, 2, 2, 4

Tags

NGSS.MS-PS1-5