Balancing Equations

In chemical reactions, what does the principle of conservation of mass mean?

• Matter is not created or destroyed.
• The total mass of the reactants is greater than the total mass of the products.
• The total mass of the reactants is less than the total mass of the products.
• Matter is not changed.
  

Tags

NGSS.HS-PS1-7

At the end of chemical reactions, what is the total mass of the reactants compared to the total mass of the products?

• the product is doubled
• the product is half the mass of the reactants
• the mass is the same
• the mass changes depending on the reaction

Tags

NGSS.HS-PS1-7

How many Elements are in the compound C₂H₈O ?

• 2
• 1
• 3
• 0

Tags

NGSS.MS-PS1-1

How many total atoms are in the compound C₂H₈O ?

• 11
• 2
• 8
• 1

Tags

NGSS.MS-PS1-1

How many Magnesium are in 10MgCl₂?

• 10
• 5
• 20

Tags

NGSS.MS-PS1-1

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.HS-PS1-7

Balance this equation.
_Mg + _Cl₂ --> _MgCl₂

• 1, 2,1
• already balanced
• 2,1,1
• 1,1,2

Tags

NGSS.HS-PS1-7

KNO₃ --> KNO₂ + O₂
What coefficients are needed to balance the reaction?

• 2, 2, 1
• 2, 3, 2
• 1, 2, 2
• 1, 3, 1

Tags

NGSS.HS-PS1-7

Balance this equation-
__P₄ + __O₂ --> __P₂O₃

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

Tags

NGSS.HS-PS1-7

Balance this equation.
_Mg + _Cl₂ --> _MgCl₂

• 1, 2,1
• already balanced
• 2,1,1
• 1,1,2

Tags

NGSS.HS-PS1-7