MS-PS1-1 Chemical Formulas

Chemical Formulas

​Representing Compounds

• Remember that compounds are found in specific ratios

• Chemical formulas are used to represent the ratio of different elements found in specific compounds

​Representing Compounds

• Elements are represented using their symbols

• Number of elements are represented using a subscript

• Example : H₂ has 2 hydrogen atoms

Open Ended

Write a chemical formula for the compound pictured

​Representing Compounds

• All elements are written together when writing a chemical formula

• Ex. H₂O NOT HOH

​Representing Compounds

• If there are multiple molecules of a single compound, the number of molecules is written before the chemical formula

• Example: 6 CO₂

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

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