History of Atomic Theory
Who was the first person to hypothesize that matter was made of small particles (atoms)?
Democritus
Draw it out! 500 points if all correct!
Make a table with the 3 subatomic particles in atoms, give the charge of each, the location of each in the atom, and the mass of each in amu.
Protons + nucleus 1 amu
Neutrons 0 nucleus 1 amu
Electrons - electron cloud 1/1850 amu
An element that becomes either positively or negatively charged by losing or gaining electrons
An ion
Where can you find the "average atomic mass" of a given element?
The periodic table
How many neutrons does hydrogen have?
zero
Who created "Atomic Theory?"
(no first name necessary)
(No...not Andy Dalton AKA "the Red Rifle"...)
John Dalton
The atomic number of an element is ALWAYS equal to its number of __.
protons
What is the name for an element that has greater or fewer numbers of neutrons (and different mass)?
isotope
What are the units for measuring atomic mass?
amu (atomic mass units)
DAILY DOUBLE! 200 points each
1) What is the term for a negatively charged ion?
2) What type of elements form negative ions?
1) anion
2) nonmetals
JJ Thompson used a cathode ray tube with an inert gas to discover what?
electrons
How many protons, neutrons, and electrons in a lithium atom?
3 protons
4 neutrons
3 electrons
How many protons, neutrons, and electrons in a carbon - 14 (C-14) isotope?
6 protons
8 neutrons
6 electrons
What is the average atomic mass of mercury?
200.592 amu
Who discovered the neutron?
Chadwick
DAILY DOUBLE! 400 points each
What did Rutherford conclude from his experiment when he shot alpha particles at a piece of gold foil?
1. atoms are mostly empty space
2. atoms have a small, dense, positively charged nucleus
How many neutrons does mercury have?
201 - 80 = 121
How many protons, neutrons, and electrons in a barium +2 (Ba+2) ion?
56 protons
81 neutrons
54 electrons
L-Cattium (Lc) was recently discovered and has 2 isotopes in nature:
Lc - 123 has a mass of 123.111 and is 85% of all L-Cattium
Lc - 129 has a mass of 128.999 and is 15% of all L-Cattium
What is the average atomic mass of L-Cattium?
Round to 3 decimal places
123.994 amu
Who discovered the proton?
Goldstein
Give the 4 parts of Dalton's Atomic Theory.
They can be in your own words.
They can be in any order.
1. Everything is made of atoms.
2. Atoms of the same element have the same properties.
3. Atoms combine in whole number ratios to make compounds.
4. Atoms combine, separate or rearrange during reactions.
DAILY DOUBLE! 500 points each
Hydrogen - 1 is over 99.9% of all the hydrogen in the universe. What are the nicknames of its isotopes (H-2 and H-3)?
H-2 is "heavy hydrogen"
H-3 is "tritium"
The Los Angeles Dodgers triple A baseball team is called the "Isotopes." What city do they play in?
Albuquerque
Lithium has 2 isotopes in nature:
Li - 6 has a mass of 6.015 amu and is 7.59% of all lithium
What is the mass of the other isotope?
Round to 3 decimals
Li - 7 = 7.016
What does the word "atom" mean in Greek?
Indivisible