3/30/2021 EOG Review

3/30/2021 EOG Review

Chemical Reactions

REACTANTS ----> PRODUCTS

Matter cannot be created OR destroyed it can only be transferred (gas created)

• Law of Conservation of Matter (matter can not be created or destroyed

• both sides of the equation must equal

Law of Conservation of Matter (Chemical Equation)

Counting atoms 2H₂O

• Subscripts: are the small numbers and belong to the ELEMENT they are behind EX. H₂

• Coefficients: Large numbers in front and multiple everything behind them EX. 2H

• 1st Count the number of Capital Letters (ELEMENTS)

• then look for subscripts and coeffiecients

Multiple Choice

Count the atoms NaOH

• Na-1

  O-1

  H-1

• N-1

  A-1

  O-1

  H-1

• Na-0

  OH-0

• Na-1

  OH-1

Multiple Choice

Count the atoms Mg(OH)₂

• Mg-1

  O-1

  H-2

• Mg-1

  O-2

  H-2

• Mg-2

  O-2

  H-2

• Mg-1

  O-0

  H-0

Multiple Choice

If a chemical reaction such as the formation of iron oxide contains 4 atoms of iron (Fe) in the product, how many atoms of iron (Fe) would be in the reactants?

• 12 atoms of iron (Fe)

• 8 atoms of iron (Fe)

• 4 atoms of iron (Fe)

• 2 atoms of iron (Fe)

MAKE SURE EACH ELEMENT IS EQUAL ON EACH SIDE

Multiple Choice

WHICH OF THESE IS A CORRECT EQUATION OF A CHEMICAL REACTION?

• NaOH+HCl --> NaCu+H₂O

• Na+ O₂+ H₂ --> NaHCl₄

• NaOH+HCl --> NaCl + H₂O

• O₂ + O₂ --> 2O₂

Multiple Choice

Which answer makes this equation correct?

___ N₂+ ___H₂ --> ___ NH₃

• 2, 2, 2

• 1, 2, 2

• 1, 3, 2

• 2, 2, 3

Multiple Choice

Which answer makes the equation correct?

___KClO₃ --> ___ KCl + ___ O₂

• 1, 2, 3

• 2, 2, 3

• 1, 1, 1

• 1, 3, 2