Chemical Formulas

Chemical Formulas

Chemical Formulas

• In chemical reactions, the atoms in molecules separate and recombine to form new compounds.

• To tell which and how many elements are in compounds, we use chemical formulas.

• Chemical formulas are a mix of element symbols and subscripts.

Chemical Formulas

• When you look at a chemical formula, it is very similar to an XYZ formula in Math class.

• Na₂SO₄

• Na₂ = 2 Sodium Atoms

• S = 1 Sulfur Atom (when there is no subscript, it is understood to be 1).

• O₄ = 4 Oxygen Atoms

Chemical Equations

• Chemical Formulas are used as a part of Chemical Equations to visualize elements in mathematical terms.

• When working with a chemical equation, you can use the chemical formulas to determine what the resulting compounds will be.

Multiple Choice

How many atoms are there TOTAL in:
H₂SO₄

• 6
• 5
• 7
• 3

Multiple Choice

Which is the correct formula for:
 three hydrogen (H)
one sulfur (S)
four oxygen (O)

• H₃SO₄
• HSO₄
• H₄S₃O
• H₂O

Multiple Choice

Which of the following is a compound?

• Co
• O₂
• C
• CO₂

Multiple Choice

Element or compound?
H₂O

• element
• compound

Multiple Choice

How many atoms of carbon (C) are in C₆H₁₂O₆?

• 3
• 6
• 12
• 24

Multiple Choice

The small number to the right of an elemental symbol  ( H₂₎ is called?

•  a subscript 
• a coefficient 
• a variable 
• a divisor