1. Look at the compound shown below then answer the questions.
BELL WORK:
Look at the compound shown below then answer the questions.
Ca2H4Cl
How many calcium atoms are there?
How many total atoms are there?
How many different elements are there?

2. TCAP Prep… What happens to atoms in a chemical reaction?
Atoms are gained.
Atoms are rearranged.
Atoms are lost.
Atoms lose mass.

3. TCAP Prep…
Which of the following is the correct chemical formula for dinitrogen tetroxide.
N4O2
NO2
N2O2
N2O4

4. TCAP Prep…
Calculate the number of atoms in the chemical formula: Na2OCl 2 5 4 3

5. WHICH COMPOUND IS IT? As a group, sort through the cards.
Three cards should be matched together.
Fill out the answer sheet when you have matched all the cards.

6. Do you remember how to count atoms?
How many oxygen atoms?
H2O2 2

7. Do you remember how to count atoms?
How many total atoms?
H2O4 6

8. Do you remember how to count atoms?
How many chlorine atoms?
Ca2Cl4 4

9. ATOMIC MODEL KITS

10. Tetrahydrogen monocarbonide
Building Atoms…
Steps:
Write the chemical formula for the problem below.
Identify each element in the compound.
Count the atoms in each formula.
Use the key and build an atom.
Draw your atom, with colors, in your notebook.
Tetrahydrogen monocarbonide

11. Check Your Work…
H4C
H=4
C=1
Total: 5