Atomic Theory
What is an atom?
Basic unit of a chemical element
Name the 3 subatomic particles
proton, neutron, electron
What are groups and periods on the periodic table?
Groups - horizontal rows
Periods - vertical columns
Define isotope
variant of an element that has the same number of protons but different number of neutrons
Define ion
atom that has gained or lost electrons
What is methane?
CH4
major component of natural gas
Describe the structure of the electron cloud.
Region around the nucleus of an atom where electrons are likely to be found, represented as a cloud.
Define valence electrons
electrons in the outermost shell
Explain why elements in the same group share similar properties
Same number of valence electrons
Describe how you get the mass number of an isotope
add the number of protons and neutrons
Describe what it means to be electrically neutral.
Equal number of protons and electrons
Hydraulic fracturing: method used to extract oil and natural gas from underground rock formations by injecting high-pressure fluid
What forces hold the atom together?
Strong nuclear force - hold protons and neutrons in the nucleus
Electromagnetic forces - keep electrons attracted to the nucleus
define quarks
particles that make up protons and neutrons
Differentiate (Describe the differences) between metals, nonmetals, and metalloids.
metals - good conductors, malleable
nonmetals - poor conductors, brittle
metalloids - chemical properties of nonmetals, physical properties of metals
What is the significance of isotopes?
Different physical properties used in applications such as dating, tracing, and medical treatments
Describe how you determine the charge of an ion.
Difference between the number of protons and electrons.
More electrons: negatively charged
Less electrons: positively charged
Describe 2 advantages and 2 disadvantages of hydrofracking.
advantages: access of huge deposits of natural gas across the US - less dependence on foreign oil, potential for new jobs
disadvantages: contamination of drinking water, large volumes of fresh water are used in the process
Draw and label the structure of an atom.
Nucleus with protons and neutrons
Electron cloud surrounding the nucleus
Describe the differences between protons, neutrons, and electrons
protons - postive charge, in nucleus
neutrons - no change, in nucleus
electrons - negative charge, surrounding space around nucleus
Describe the difference between atomic number and mass number.
atomic number - on periodic table, number of protons in atom
mass number - not on periodic table, sum of protons and neutrons
Identify the isotope (nulear notation) and the subatomic particles with the following:
atomic number = 31
mass number = 59
59Ga
protons - 31
neutrons - 28
electrons - 31
What is the charge of an ion that has the following:
15 protons
14 neutrons
13 electrons
+2
Describe the differences between thermogenic and biogenic methane.
thermogenic methane: formed millions of years ago and is found at greater depths and pressure. Typically what is tapped by commerical drilling
biogenic methane: produced by bacteria
Name of the scientist for the model of the atom
Bohr
Proton - identity
Neutron - mass
Electron - bonding behavior
helium - 2
2He
Name the instrument that is used to identify isotopes.
Mass spectrometer
Identify the ion (nulear notation) and the subatomic particles with the following:
atomic number = 31
mass number = 59
charge = 3+
59Ga3+
proton - 31
neutron - 28
electron - 28
Describe how hydrofracking is related to our unit on the atom.
The abundance of carbons-12 and carbon-14 are different between thermogenic and biogenic methane which allows us to determine if methane is coming from hydrorfracking. We learned about isotopes in this unit.