Atomic Structure
Ions & Isotopes
Average Atomic Mass
Nuclear Decay & Half Life
History of the Atom
100
What subatomic particle is NOT found in the nucleus?
electrons
100
Isotopes have the same number of _______ but a different number of __________
Protons, neutrons
100
Which subatomic particles have a mass of 1 amu?
Protons and neutrons
100
Which is the largest radiation particle (the heaviest)?
Alpha
100
Rutherford’s gold foil experiment lead to the discovery of….?
The nucleus
200
What is the charge of a proton, neutron, and electron?
Proton = positive charge
Neutron = no charge / neutral charge
Electron = negative charge
200
What is the name of a positively charged ion?
Cation
200
Helium has two naturally occurring isotopes, He-3 and He-4. The atomic mass of helium is 4.003 amu. Which isotope is more abundant in nature?
He-4
200
Fusion or Fission?
Fission
200
Who is responsible for the discovery of the electron using the cathode ray tube?
JJ Thomson
300
What subatomic particle never changes in atoms of the same element?
Protons
300
C-12 and C-14 are examples of what?
Isotopes
300
Calculate relative abundance for each of the isotopes.
Isotope Mass (amu) % Abundance
Mg-24 23.985 78.70%
Mg-25 24.986 10.13%
Mg-26 25.963 11.17%
Mg-24 = 0.7870
Mg-25 = 0.1013
Mg-26 = 0.1117
300
Predict the product for Actinium undergoing alpha decay
206
Fr
300
Who created the model in which he claimed electrons orbit the nucleus in circles and specific energy levels?
Niels Bohr
400
An element has 8 protons, 8 electrons, and 9 neutrons. What is its mass number?
17
400
If sodium has 10 electrons, what is its charge?
+1
400
Calculate relative mass for each of the isotopes.
Isotope Mass (amu) % Abundance
Mg-24 23.985 78.70%
Mg-25 24.986 10.13%
Mg-26 25.963 11.17%
Mg-24 0.7870 x 23.985 = 18.8762
Mg-25 0.1013 x 24.986 = 2.53108
Mg-26 0.1117 x 25.963 = 2.90007
400
Predict the product for Neon undergoing beta decay.
25
Na
400
Who first proposed an atomic theory based on scientific knowledge?
Dalton
500
How many protons, neutrons, and electrons are in a neutral Bromine atom?
P = 35 N = 45 E = 35
500
Identify the element and write the nuclear notation for this atom.
55 3+
Fe
26
500
Calculate average atomic mass (Include UNITS and SIG FIGS).
Isotope Mass (amu) % Abundance
Ag-107 107 51.86%
Ag-109 109 48.14%
(0.5186)(107 amu) + (0.4814)(109 amu) =
55.4902 amu + 52.4726 amu = 108 amu
500
Os-182 has a half-life of 21.5 hours. How many grams of a 10.0 gram sample is left after 86.0 hours? Show your work. Use correct sig figs & units.
0.625 g
500
Who created the modern periodic table?
Moseley