Download 1.1 Guided Reading

1.1
Guided Reading:
Atoms are the smallest form of elements.
Name __________________________ Period _____ Number _____
DIRECTIONS: As you read pages 9 through 13, answer the
questions in COMPLETE SENTENCES!!
All matter is made of atoms. (page 9)
1. What did Greek philosophers propose about 2,400 years
ago?
2. Today, what do modern chemists know?
3. What 2 ways can elements around you appear?
Types of Atoms in Earth’s Crust and Living Things (p.10)
4. What is the most abundant atom in the UNIVERSE?
5. What is the most abundant atom in the EARTH’S CRUST?
6. Which 4 atoms are living things primarily
composed?
Names and Symbols of Elements (page 10)
7. How did each element get its name?
a. Lithium:
b. Neptunium:
c. Magnesium:
8. Why is the symbol for gold Au?
9. The symbol for lead is ______, and the symbol for iron
is ________. The symbols of these elements come from
_______________names.
Each element is made of a different atom. (page 11)
10. What 3 ideas did 1800s British scientist John Dalton
propose?
A.
B.
C.
11. Which part (see #10) of Dalton’s theory was proven false
by scientists?
The Structure of an Atom (page 11)
12. What key discovery led to the current model of the atom?
13. Name the 3 particles that make up an atom.
14. A. Where are protons located, and what kind of charge do they have?
B. Where are neutrons located, and what kind of charge do they
have?
C. Draw a diagram of the nucleus of lithium. One atom of lithium
has 3 protons and 4 neutrons. (look at page 11—bottom)
15. How much bigger is the electron cloud compared to an atom’s
nucleus?
16. How much smaller are electrons compared to protons and neutrons?
17.
Why do the negative electrons stay in place (remain associated)?
18. Neutral atoms have the same number of which 2 particles?
ILLUSTRATING THE CONCEPTS:
19. Use the pie chart on page 10 to complete the missing information. Each
segment of the chart should be colored a different color and include the
percentage.
Atom Concentration By Mass: Earth’s Crust
Oxygen
Iron
Aluminum
Silicon
Other
Atom Concentration By Mass: Humans
Oxygen
Nitrogen
Carbon
Hydrogen
Other
Atomic Numbers
Atomic Mass Numbers
Isotopes
(page 12-13)
20. The identity (name) of an atom is determined by the
number of __________________ in its nucleus. This is also
called its ___________________ number.
21. Use the periodic table on page 20-21 to identify the
atoms (elements) that have
a. 13 protons, or atomic number 13: _________________
b. 22 protons, or atomic number 22: _________________
22. What is atomic mass number (aka “mass number”)?
23. All atoms of the same element will always have the same
number of which particle?
24. However, some atoms have isotopes. What is an isotope?
25. Make a neat diagram of Chlorine-35 and Chlorine—37.
Be sure to label the protons, neutrons, electrons, and the
nucleus. (see page 13)
Chlorine--35
Chlorine—37
26. (Bonus Coupon Question---not required)
Research the common isotopes of carbon or hydrogen. Make a
diagram of them below.