atoms & their structure chapter 2 section 1 part 3
TRANSCRIPT
![Page 1: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/1.jpg)
Atoms & Their StructureChapter 2 Section 1
Part 3
![Page 2: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/2.jpg)
Objectives
What information is available in an element block of the periodic table?
![Page 3: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/3.jpg)
Important Vocabulary Atomic number Mass number Atomic mass unit Atomic mass Isotopes
![Page 4: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/4.jpg)
The Modern Periodic Table
The modern periodic table has 118 elements Only 114 have official names It groups similar elements together The organization makes it easier to predict
the properties of elements Elements are represented by their symbols Position in the table helps to determine
properties of elements The order of arrangement is based on
the number of protons an atom of that element has in the nucleus
![Page 5: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/5.jpg)
![Page 6: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/6.jpg)
Reading The Periodic Table
![Page 7: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/7.jpg)
Information from the PT Atomic number (Z) equals the
number of protons as well as the number of electrons
Mass number (A) equals the total number of subatomic particles in the nucleus The number of protons & neutrons
Mass number – atomic number = # of neutrons
![Page 8: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/8.jpg)
The Mass of an Atom Is very small We usually work with atomic mass units Atomic mass unit (amu) is equal to
one-twelfth of the mass of carbon-12 atom
Average atomic mass is a weighted average of the masses of all naturally occurring isotopes of an element
The more common the isotope the greater the effect on the average
![Page 9: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/9.jpg)
Isotopes Are atoms of the same element that
differ by the number of neutrons in the nucleus
They DO NOT differ in atomic number They ONLY differ in mass number & their
physical properties
![Page 10: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/10.jpg)
Mass of an Atoms
![Page 11: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/11.jpg)
Calculating the # of Neutrons
![Page 12: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/12.jpg)
Practice! Calculate the # of protons,
electrons, & neutrons in the following isotopes
1. Carbon-14
2. Nitrogen-15
3. Sulfur-35
4. Calcium-45
5. Iodine-131
![Page 13: Atoms & Their Structure Chapter 2 Section 1 Part 3](https://reader036.vdocuments.us/reader036/viewer/2022062322/5697bfa61a28abf838c9885f/html5/thumbnails/13.jpg)
Practice!-Answers
Carbon-14: P = 6 E = 6 N = 8
Nitrogen-15: P = 7 E = 7 N = 8
Sulfur-35: P = 16 E = 16 N = 19
Calcium-45: P = 20 E = 20 N = 25
Iodine-131: P = 53 E = 53 N = 78