balancing

 Mg  +  ___ HCl  →   MgCl₂  +   H₂

• 1
• 2
• 3
• 4

Which side of a chemical equation is the reactant side?

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

Which side of a chemical equation os the product side?

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

Which problem is balanced?

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

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

• Coefficient 
• Subscript
• Atom
• Equation

What does the Law of Conservation of Mass state?

• Matter cannot be gained or lost in a chemical reaction.
• Matter can only be lost in a chemical reaction.
• Matter can only be gained in a chemical reaction.
• Matter can be gained and lost in a chemical reaction. 

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

• Yes
• No

Balance this equation
_Al +_HCl --> _H₂ +_AlCl₃

• 2, 6, 3, 2
• it is already balanced
• 4, 12, 3, 4
• 2, 1, 4, 5

Balance this equation.
_CF₄ + _Br₂ -- _CBr₄ + _F₂

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

How many atoms of aluminum are on each side of the following equation: 4Al + 3O₂ --> 2Al₂ O₃

• 2
• 6
• 1
• 4