What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The...
-
Upload
gervase-taylor -
Category
Documents
-
view
238 -
download
0
Transcript of What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The...
![Page 1: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/1.jpg)
What do atoms look like?
![Page 2: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/2.jpg)
What do we know about atoms?
*All elements are composed of atoms*The atoms of the same element are the same (and different from the atoms of any other element)*Atoms of different elements can mix together or can chemically combine in a whole number ratio to form compounds* Chemical reactions occur when atoms are joined, separated or rearranged. BUT you can’t turn one element into another by chemical reaction.
![Page 3: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/3.jpg)
What are atoms made of?
• The three basic components of an atom are the
–Proton
–Neutron
–Electron
![Page 4: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/4.jpg)
Where are the subatomic particles found?
• Proton
• Neutron
• electron
![Page 5: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/5.jpg)
![Page 6: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/6.jpg)
![Page 7: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/7.jpg)
• Found in the nucleus
• Has a +1 charge
• Mass of ~1amu
• 10-15 m in size
• p+
![Page 8: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/8.jpg)
• Found in the nucleus
• Electrically neutral
• Mass of ~1amu
• 10-15 m in size
• n5
![Page 9: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/9.jpg)
• Found outside the nucleus in the “electron cloud”
• Has a -1 charge
• Mass of ~0
• 10-18 m in size
• e-
![Page 10: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/10.jpg)
MASS?
1 amu or “atomic mass unit” is 1/12 the mass of carbon 12
![Page 11: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/11.jpg)
SIZE?
• The empty atom: If we imagine the atom’s nucleus to be the size of a bean, the atom itself will become the size of a stadium, and the electrons will be like tiny fleas whizzing frantically somewhere around the stands.
![Page 12: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/12.jpg)
What makes the atoms of one element different from the atoms of
another?• The number of protons, neutron, and
electrons differs from one element to the next.
• The number of determines the element.
• The number of protons is equal to the on the periodic table
![Page 13: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/13.jpg)
6
C12.011
Carbon
![Page 14: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/14.jpg)
Atomic Number = # of Protons
• Every Hydrogen atom has ____ protons
• Every Magnesium atom has ____ protons
• Every Arsenic atom has ____ protons
![Page 15: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/15.jpg)
Atoms are electrically neutral so…
# of protons must = # of electrons
How many electrons in an atom of Hydrogen?
Magnesium?
Arsenic?
![Page 16: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/16.jpg)
The mass of an atom comes from its protons and neutrons so…
Mass Number = # of protons + # of neutrons
Or
Mass number – atomic number = # of neutrons
![Page 17: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/17.jpg)
What is the difference between mass number and atomic mass?
• Atomic Mass= weighted average of the masses of all known isotopes of an element.
• Mass Number = protons + neutrons for a particular isotope of an element
***Round atomic mass to the nearest whole number to get the mass number for the most common isotope of that element.
![Page 18: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/18.jpg)
How many neutrons in an atom of
Hydrogen?
Magnesium?
Arsenic?
Round the atomic mass to the nearest whole number
![Page 19: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/19.jpg)
Why isn’t atomic mass a whole number?
Because elements exist as
Atoms with the same number of protons BUT a different number of neutrons
All atoms are isotopes, some are just more common then others!!!
Atomic mass is the weighted average of all the known isotopes of an element.
![Page 20: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/20.jpg)
Isotopes are often represented using isotopic notation:
Mass number
Atomic number
Element symbol14
6
CEx.
![Page 21: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/21.jpg)
• Many times the atomic number will be left off (since that always remains the same)
ex. Carbon-14
or14C
Did you know that carbon -14 is used to date fossils!
• Many times the atomic number will be left off (since that always remains the same)
ex. Carbon-14
or14C
![Page 22: What do atoms look like?. What do we know about atoms? *All elements are composed of atoms *The atoms of the same element are the same (and different.](https://reader036.fdocuments.us/reader036/viewer/2022062423/56649edb5503460f94beafce/html5/thumbnails/22.jpg)
What about IONS?
• Ions are electrically charged atoms
Positive = cation = more protons then electrons
Negative = anion = more electrons then protons
Represented as K+1