Calculate how many moles of atoms are in 6.22 g of gold.
0.0316 mol
100
Give the electron configuration of silicon.
1s2 2s2 2p6 3s2 3p2
100
What type of compound is this?
PbCr2O7
Ionic
100
3Cl2(g) + 6OH-(aq) → ClO3-(aq) + 5Cl-(aq) + 3H2O(l)
What will happen to the relative concentrations of reactants and products in this reaction if I remove some of the water?
Concentration of product will go up.
Concentration of reactants will do down.
100
In the following reaction which is the oxidizing agent?
2H+(aq) + Pb(s) → H2(g) + Pb2+(aq)
H+(aq)
200
How many sodium atoms are in 15.0 g of sodium chloride?
7.73x10^22 atoms
200
What is the electron configuration of lead?
[Xe] 6s2 4f14 5d10 6p2
200
What types of intermolecular forces are present in this compound?
CH3CH2NH2
hydrogen bonding, London dispersion forces
200
Which is colder, a 5 gallon bucket filled half way with ice and the other half with water or a glass of water with a few ice cubes in it?
They are the same temperature.
200
Find the potential of the following voltaic cell.
Fe2+/Fe and Zn2+/Zn
0.323 V
300
Look at the reaction below.
2Al(s) + 2NaOH(aq) + 6H2O(l) → 2Na+(aq) + 2[Al(OH)4]-(aq) + 3H2(g)
What volume of H2 gas is produced from this reaction when 25.0 g of aluminum is used? (at 1.3 atm and 25oC)
26.1 L
300
Order the following in terms of increasing atomic radius:
Carbon, aluminum, oxygen, potassium
K>Al>C>O
300
Which has the lowest freezing point?
H2, CH4, or CO
H2
300
Calculate the heat of formation of ethanol (CH3CH2OH) given the following data.
Heat of Combustion of ethanol = -1371 kJ/mol
Heat of formation of water = -285.8 kJ/mol
Heat of formation of carbon dioxide = -393.5 kJ/mol
-277 kJ/mol
300
What is the half reaction that occurs at the anode in the following voltaic cell?
I2/I- and Ni2+/Ni
Ni2+(aq) + 2e- → Ni(s)
400
3Co(s) + 4O2(g) → 2Co3O4(s)
If you have 52.2 g of O2 gas and 24.6 g of Co which is the limiting reactant?
Co
400
Which has a higher first ionization energy, magnesium or sodium?
Mg
400
Which of these compounds would be most soluble in water?
(CH3)2O or CH3CH2OH
CH3CH2OH
400
The heat released from the combustion of coal is used to create steam that spins a turbine thereby generating electricity. The heat of formation of carbon dioxide is -393.5 kJ/mol. How many kilograms of coal are needed to turn 150 L of water at 100 oC into steam? The heat of vaporization of water is 40.79 kJ/mol.
38 kg
400
Assign oxidation numbers to all the elements in the following reaction and determine what is being oxidized and what is being reduced.
Mg(s) + H2SO4(aq) → MgSO4(aq) + H2(g)
Mg is oxidized
H is reduced
500
An element crystallizes in a body-centered
cubic lattice. The edge of the unit cell is 2.86 A,
and the density of the crystal is 7.92 g/cm3.
Calculate the atomic weight of the element.
55.78 g/mol
500
Which is bigger, Cl- or K+?
Cl-
500
Draw all the structural isomers of the compound with the formula C4H10.
On board
500
The enthalpy change for the following reaction is +14.7 kJ/mol and the entropy change is +50.1 J/K. Below what temperature is this reaction no longer spontaneous?
NH4Cl(s) ----> NH4 + (aq) + Cl - (aq)
293 K
500
Antioxidants work by reacting with harmful oxygen free radicals in your body, preventing damage to your cells' DNA. Are antioxidants reducing or oxidizing agents?