Elements and Atoms
Bonds and Molecules
Gas Laws
Concentrations
Misc.
100
What are the three primary components of an atom?
Protons, neutrons, and electrons. Protons and neutrons make up most of the mass. Protons and electrons carry the charge.
100
What kind of bonding involves trading electrons between atoms from opposite sides of the periodic table?
Ionic bonding occurs when atoms from opposite sides of the periodic table fulfill their outer electron shells by stealing electrons. The most electronegative atoms (far right of periodic table) only need 1-3 electrons to fill the outer shell while the least electronegative (far left of periodic table) yield electrons.
100
The universal gas constant (R) is equal to:
0.08206 L atm /(K mol)
100
Define the terms solute and solvent.
A solute is a species dissolved or dispersed in another material known as the solvent.
100
If 1 mg/L is a part per million (ppm) then 1 ug/L is a ?
1 ug/l is a part per billion or ppb.
200
What is the atomic number of silicon (the most abundant element at Earth's surface)
14 atomic number = number of protons in the element
200
Where on the periodic table are the elements prone to sharing electrons freely generating electric current?
Metallic bonds occur when pure metals (middle right of periodic table) allow electrons to flow from atom to atom. The flow of electrons is electric current.
200
Conditions of standard temperature and pressure are:
O degrees C (273.15 K) and 1 atm are considered STP.
200
What is the molarity of a 4 mg/L solution of H2SO4?
Molarity is the number of moles per volume. 4 mg/L H2SO4 X (1 mole/1.00+1.00+32.06+4*15.99g)*1g/1000mg =4.08 x 10 ^-5 mol/L
200
Balance the chemical reaction: Al(OH)3 + H+ --> Al3+ + H2O
2Al(OH)3 + 6H+ --> 2Al3+ + 6H2O
300
Carbon 14 is a(n)___________of Carbon.
Isotope Isotopes are atoms with the same number of protons but different numbers of neutrons. Because neutrons have mass, the atomic weight of isotopes differ. An element is identified (given and atomic number) by the number of protons in the nucleus.
300
What type of bind is formed when hydrogen bonded to a polar atom in one molecule nears a polar atom of another molecule?
A hydrogen bond, which is a specific kind of Van der Waal's bonding.
300
The molar volume of an ideal gas is?
22.41 L/mol or 22.41 x 10^-3 m^3/mol
300
What is the equivalent weight of sodium in sodium carbonate (NaCO3)?
Equivalent weights are a handy measure for species whose reactivity is mostly due to valance. It is equal to the atomic or molecular weight in grams divided by the valence. Na = 22.99/2=11.54 Equivalent weights are a useful way to determine how much acid or base is produced when a compound is dissolved in water. For example, there are two gram equivalent weights of H+ in NaCO3.
300
A chemical analysis for a material gives 82.659% Carbon and 17.341% Hydrogen. The molecular weight of the compound if 58.123g. What is the empirical formula for the compound? What is the molecular formula for the compound?
The empirical formula is the lowest whole number ratio of elements in a molecule. = C2H5 The molecular formula is the whole number ratio of the atoms as they occur in the molecule. = C4H10
400
What property increases to the right and top of the periodic table? Elements that have this property include Oxygen, Nitrogen, Chlorine and Florine.
Electronegativity describes and atoms's ability to draw an electron from another atom. These elements act as electron thieves and are very important in the environment.
400
Which type of bonds occur when atoms share electrons?
Covalent bonding occurs when atoms share electrons. In atomic orbital theory these bonds involve overlapping orbitals. They tend to occur between atoms close to one another on the periodic table.
400
Explain why solid water (ice) is less dense than liquid water?
The density of ice is lower than that of liquid water because in its solid structure the ice preserves the most ideal arrangement of water molecules. In this case, the molecules are arranged in coordinating hexagonal rings of alternating H ad O atoms.
400
A 2L solution contains 85g of LiCl. Calculate the mass of Cl in the solution.
About 71 g of Cl are present in the 2L solution of LiCl.
400
The picture on the cover of the textbook was taken where?
In Yellowstone National park at Grand Prismatic Spring. The colors originate from algae and bacteria in the water.
500
What are the three rules for modern atomic orbital theiry?
1. electrons fill the lowest energy orbitals first to minimize atomic energy. 2. Electrons enter each available orbit singly. After the available orbits are singly filled electrons with opposite spins may enter. 3. Atoms achieve maximum stability when orbitals ar empty, half filled or full.
500
How many molecules are in 1 gram of potassium bromide (KBr)?
5.1 x 10^21
500
The ideal gas law (PV=nRT) can be reaaranged so that n/V = P/RT. What does n?V also represent?
Molar concentration. n is the number of moles and V is the volume of solution.
500
What is the normality of a 2 x 10-3 mol/L BaSO4 solution?
2x10^-3 mol/L BaSO4 * 2 charges per mol =1x10^-3 charges per liter so it is 4 x 10^-3 Normal.
500
The best ways to get an A in this class are?
-Come to class -Do your homework individually (try it alone before discussing with others) -Read according to the syllabus -Try some of the examples as you read -ask questions
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