Download atom book - District 196

Name ___________________________________________________________ Hour _____________
ATOM BOOK ASSIGNMENT
p. 134
1. There are ___________ naturally occurring elements plus another _______ that have been
created in a laboratory.
Atomic Theory: (p. 135-136)
2. _____________________________ was a Greek philosopher who proposed the idea that you
must reach a smallest indivisible part of a substance. He named it an “atom”.
3. In 1808 ________________________ came up with the first MODERN ATOMIC THEORY which
had 4 parts:
a. All elements are made of indivisible particles called ____________________
b. All atoms of the same element are ______________ but are different from other
elements.
c. Reactions ____________________ atoms but do not create or destroy them.
d. _______________________ are made from combining atoms in whole number ratios
4. In 1897 J. J. Thomson discovered the negatively charged ____________________ while
experimenting with cathode rays.
5. In 1910, Ernest Rutherford carried out the gold foil experiment in which he determined
that atoms have nearly all their mass concentrated in a very tiny, very dense,
____________________________ charged nucleus.
The inside of an atom: (p. 137-141)
6. Which particles are found in the nucleus?
7. Most of an atom’s mass is concentrated in the ______________________8. In the carbon atom __________% of the mass is from the nucleus.
9. What is the atomic number equal to? ______________________________________________
10. What is an isotope?
11. The mass number is equal to the _________________ + the _____________________
12. The average atomic mass is a decimal because of a mixture of ____________________
13. Because an electron is much lighter than a proton or neutron, is it also much __________
and has a wider range than just the nucleus.
14. The size of an atom is really the size of its ____________________ cloud.
15. Besides mass, virtually every property of atoms is determined by electrons, including
__________________ and chemical _________________________.
16. The charge on the electron and the proton are exactly __________________ and
________________________ so the charge on a complete atom is always _________.
Name ___________________________________________________________ Hour _____________
Use p. 135-136 to describe the following scientific experiments: Include what happened and
what was discovered about the atom.
1. J. J. Thomson’s cathode ray:
2. Ernest Rutherford’s Gold Foil experiment:
Read through John Dalton’s 4 ideas on p. 125 and use what you know about an atom to
determine which 2 are incorrect.
#1 is
correct /
incorrect
because:
#2 is
correct /
incorrect
because:
#3 is
correct /
incorrect
because:
#4 is
correct /
incorrect
because: