INDEPENDENT PRACTICE
See Example 1
Write each number in standard notation.
11. 9.2 106
See Example 2
See Example 4
13. 3.6 102
14. 5.24 108
Write each number in scientific notation.
15. 0.00007
See Example 3
12. 6.7 104
16. 6,500,000
17. 100,000,000
19. Protons and neutrons are the most massive
particles in the nucleus of an atom. If a
nucleus were the size of an average grape,
it would have a mass greater than 9 million
metric tons. A metric ton is 1000 kg. What
would the mass of a grape-size nucleus
be in kilograms? Write your answer in
scientific notation.
18. 0.00000003
Atom
Electron
Proton
Neutron
Nucleus
20. The orbits of Neptune and Pluto cross each
other. Neptune’s average distance from the Sun is approximately
4.5 109 kilometers. Pluto’s average distance from the Sun is
approximately 5.87 109 kilometers. Which object has the greater
average distance from the Sun?
PRACTICE AND PROBLEM SOLVING
Extra Practice
Write each number in standard notation.
See page EP8.
21. 1.4 105
22. 3.24 102
23. 7.8 101
24. 2.1 106
25. 5.3 108
26. 8.456 104
27. 5.59 105
28. 7.1 103
29. 7.113 106
30. 4.5 101
31. 2.9 104
32. 5.6 102
Life Science
33. Life Science Duckweed plants live on the surface of calm ponds and are
the smallest flowering plants in the world. They weigh about 0.00015 g.
a. Write this number in scientific notation.
b. If left unchecked, one duckweed plant, which reproduces every
30–36 hours, could produce 1 1030 (a nonillion) plants in four
months. How much would one nonillion duckweed plants weigh?
This frog is
covered with
duckweed plants.
Duckweed plants
can grow both in
sunlight and in
shade and
produce tiny
white flowers.
34. Life Science The diameter of a human red blood cell ranges from
approximately 6 106 to 8 106 meters. Write this range in standard
notation.
35. Physical Science The atomic mass of an element is the mass, in grams,
of one mole (mol), or 6.02 1023 atoms.
a. How many atoms are there in 2.5 mol of helium?
b. If you know that 2.5 mol of helium weighs 10 grams, what is the atomic
mass of helium?
c. Using your answer from part b, find the approximate mass of one atom
of helium.
4-4 Scientific Notation
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