The document provides information about compounds and their formulas. It explains that subscripts in formulas indicate the number of atoms present of each element in a compound. Examples are given of common compounds like calcium carbonate (CaCO3), magnesium hydroxide (Mg(OH)2), and trinitrotoluene explosive (C7H5(NO2)3). The main elements that make up living organisms are identified as carbon, phosphorus, hydrogen, oxygen, nitrogen and sulfur. The document also lists common unit labels for mass, volume, and density.

1. You Will Need:
1. Interactive Reader Pgs. 139-
143 – Due Now- Middle Table
2. Worksheet – Due Now – Turn
in Tray
3. Atoms-Building Blocks of
Matter – Counting Atoms
Bookshelf – Please Staple

2. The formula for a compound indicates the elements
that make up the compound and the number of
atoms of each element present in that specific
compound. These numbers of atoms are
indicated by the use of small numbers called
subscripts.

3. When a subscript appears outside the
parentheses, it indicates that all the elements
inside the parentheses should be multiplied by
that subscript.
Fe(OH) 3

4. • Calcium Carbonate = Limestone
CaCO3
Ca = Calcium = 1
C = Carbon = 1
O = Oxygen = 3

5. • Magnesium Hydroxide
Mg(OH)2
Mg = Magnesium= 1
O = Oxygen= 2
H = Hydrogen= 2

6. Trinitrotoluene = (TNT) explosive
C7H5(NO2)3
C= Carbon = 7
H = Hydrogen = 5
N = Nitrogen = 3
O = Oxygen = 6

7. As you look over these compounds you
may observe that many of them contain
atoms
similar _________ of elements. Since
carbon
we are a ______________ based
environment, carbon is found in all living
organisms. The elements in the Human
Body can be broken down to include the
main elements of Hydrogen, Oxygen,
Nitrogen, Carbon and representatives
from about 20 other elements.

8. SIX
The _________ main elements that
make up most living organisms are
Phosphorus
Carbon, ________________, Sulfur,
Hydrogen
__________________, Oxygen and
Nitrogen
_____________.

9. grams
•Mass Unit Label =_______________
cm 3
•Volume Unit Labels = ________,
mL cc
_______ or _______as a unit label
g/cm 3
•Density unit label = ___________,
g/mL g/cc
________ or __________

10. 5 points given:
• 2 points for the problem you are
inputting into the calculator
• 2 points for the answer rounded
to the nearest hundreth
• 1 point for the unit label

11. 1. Counting Atoms – Due by
the end of the period
tomorrow
2. Anything you still owe
me….