Table of contents

1. Introduction to Biology2h 40m
2. Chemistry3h 40m
3. Water1h 26m
4. Biomolecules2h 23m
5. Cell Components2h 26m
6. The Membrane2h 31m
7. Energy and Metabolism2h 0m
8. Respiration2h 40m
9. Photosynthesis2h 49m
10. Cell Signaling59m
11. Cell Division2h 47m
12. Meiosis2h 0m
13. Mendelian Genetics4h 41m
14. DNA Synthesis2h 27m
15. Gene Expression3h 20m
16. Regulation of Expression3h 31m
17. Viruses37m
- Viruses
  37m
18. Biotechnology2h 58m
19. Genomics17m
- Genomes
  17m
20. Development1h 5m
21. Evolution3h 1m
22. Evolution of Populations3h 52m
23. Speciation1h 37m
24. History of Life on Earth2h 6m
25. Phylogeny2h 31m
26. Prokaryotes4h 59m
27. Protists1h 12m
28. Plants1h 22m
29. Fungi36m
- Fungi
  19m
- Fungi Reproduction
  17m
30. Overview of Animals34m
- Overview of Animals
  34m
31. Invertebrates1h 2m
32. Vertebrates50m
33. Plant Anatomy1h 3m
34. Vascular Plant Transport2m
- Water Potential
  2m
35. Soil37m
- Soil and Nutrients
  20m
- Nitrogen Fixation
  16m
36. Plant Reproduction47m
- Flowers
  33m
- Seeds
  14m
37. Plant Sensation and Response1h 9m
38. Animal Form and Function1h 19m
39. Digestive System10m
- Digestion
  3m
- Blood Sugar Homeostasis
  7m
40. Circulatory System1h 57m
41. Immune System1h 12m
42. Osmoregulation and Excretion50m
- Osmoregulation and Excretion
  50m
43. Endocrine System4m
- Endocrine System
  4m
44. Animal Reproduction2m
- Animal Reproduction
  2m
45. Nervous System55m
- Neurons and Action Potentials
  8m
- Central and Peripheral Nervous System
  46m
46. Sensory Systems46m
- Sensory System
  46m
47. Muscle Systems23m
- Musculoskeletal System
  23m
48. Ecology3h 11m
49. Animal Behavior28m
- Animal Behavior
  28m
50. Population Ecology3h 41m
51. Community Ecology2h 46m
52. Ecosystems2h 36m
53. Conservation Biology24m
- Conservation Biology
  24m

2. Chemistry

Isotopes

General Biology

2. Chemistry

Isotopes

3:05 minutes

Problem 6Campbell - 11th Edition

Textbook Question

We can represent atoms by listing the number of protons, neutrons, and electrons—for example, 2p+,2n0,2e− for helium. Which of the following represents the 18O isotope of oxygen? a. 7p+,2n0,9e− b. 8p+,10n0,8e− c. 9p+,9n0,9e− d. 10p+,8n0,9e-

Verified step by step guidance

Identify the atomic number of oxygen, which is 8. This number represents the number of protons in an oxygen atom.

Understand that the number of electrons in a neutral atom equals the number of protons. Therefore, an oxygen atom also has 8 electrons.

Recognize that the notation 18O refers to an isotope of oxygen where the total number of protons and neutrons equals 18. Since there are 8 protons in oxygen, subtract 8 from 18 to find the number of neutrons: 18 - 8 = 10 neutrons.

Review the options given and find which one correctly lists 8 protons, 10 neutrons, and 8 electrons. This matches the description of the 18O isotope.

Select option b. 8p+,10n0,8e− as it correctly represents the 18O isotope of oxygen with 8 protons, 10 neutrons, and 8 electrons.

Recommended similar problem, with video answer:

Verified Solution

This video solution was recommended by our tutors as helpful for the problem above

Video duration:

Play a video:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Atomic Structure

Atoms consist of protons, neutrons, and electrons. Protons are positively charged and found in the nucleus, neutrons are neutral and also located in the nucleus, while electrons are negatively charged and orbit the nucleus. The number of protons defines the element, while the number of neutrons can vary, leading to different isotopes of the same element.

Isotopes

Isotopes are variants of a particular chemical element that have the same number of protons but different numbers of neutrons. This difference in neutron count results in varying atomic masses. For example, oxygen has several isotopes, including 16O, 17O, and 18O, with 18O having two more neutrons than the most common isotope, 16O.

Notation of Isotopes

Isotopes are often represented using a notation that includes the element symbol and the mass number, which is the sum of protons and neutrons. For instance, 18O indicates an oxygen atom with 8 protons and 10 neutrons (8 + 10 = 18). Understanding this notation is crucial for identifying isotopes and their properties in various contexts.

Watch next

Master Isotopes with a bite sized video explanation from Jason Amores Sumpter

Start learning

Related Videos

Related Practice

Multiple Choice

What is TRUE about carbon-13 and carbon-14?

a) They are isotopes.

b) They have the same mass number.

c) They have the same number of neutrons in their nuclei.

d) They behave differently in biological reactions.

e) None of the above are true.

How are Carbon-13 and Nitrogen-15 respectively different from the more abundant isotopes Carbon-12 and Nitrogen-14? Carbon-13 and Nitrogen-15 _______________:

a) Each have an extra neutron.

b) Each have an extra proton.

c) Each have one less neutron.

d) Each have one less proton.

e) Each have one less electron.

The atomic number of nitrogen is 7. Nitrogen-15 has a greater mass number than nitrogen-14 because the atomic nucleus of nitrogen-15 contains ________.

a) 7 neutrons.

b) 8 neutrons.

c) 8 protons.

d) 15 protons.

Radioactive isotopes are utilized for all of the following except:

a) Dating fossilized material of once living things.

b) Radiation treatment to slow or stop the development of cancer cells.

c) Labeling regions of the body with radioactivity for special imaging techniques.