Week 1 - CHEM 121 Review
Week 2 - Lewis Structures and Molecular Geometry
Week 3 - Intermolecular Forces
Week 4 - Chemical Reactions and Stoichiometry
Week 5 - Molecular Formula, Limiting Reactant, and Percent Yield
100
What is the density of a substance with a mass of 46.345g and displaces 6.5mL of water in a graduated cylinder?
7.13g/cm3
100
How many valence electrons does sulfur have?
6
100
Which molecules have London Dispersion Forces?
A. CO2
B. H2O
C. HF
D. MgS
All molecules exhibit LDF.
100
What are the coefficients needed to balance the equation?
Al + O2 ---> Al2O3
4, 3, 2
100
What is the molecular formula for a CH2O with a molecular mass of 90g/mol?
C3H6O3
200
Calculate the molar mass of H2SO4.
98.07
200
What is the bonding capacity of boron?
3
200
Hydrogen bonds require what?
Hydrogen must be bonded to N, O, or F.
200
Where do you get the information for:
A. Molar Mass
B. Mole Ratio
C. Calculating the number of molecules, atoms, or particles
A. Periodic table
B. Balanced chemical equation (RXN)
C. Avagadro's number, 6.022x1023
200
What is the empirical formula of glucose, which contains 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen.
CH2O
300
What is the element and charge on an ion that has 24 protons, a mass number of 52, and 20 electrons?
Cr4+
300
What is the steric number of ammonia, NH3?
SN = 4
300
Using the phase diagram below, give any temperature and pressure where CO2 would be in the liquid phase.
Temp between -56.7C and 31C
Pressure between 5.1atm and 72.9atm
300
If you start with 37.0g of water, how many moles of sodium will it react with?
Na + H2O ---> NaOH + H2
2.1mol Na
300
What is percent composition of a lab sample containing 24.02g carbon and 64.00g oxygen?
27.29% C
72.71% O
400
What is the electron configuration for aluminium?
1s22s22p63s23p1 or [Ne]3s23p1
400
What is the electron-pair geometry and molecular geometry of SO2?
Electron-pair geometry: Trigonal planar
Molecular geometry: Bent (angular)
400
Which of the following molecules are polar?
A. CS2
B. H2O
C. HF
D. O2
H2O, HF
400
Some cars use butane (C4H10) as fuel:
2C4H10 + 13O2 ---> 8 CO2 + 10H2O
How many grams of H2O are produced when 5.38g of O2 is reacted?
2.33g H2O
400
For the reaction below, 1.56g of BaCl2 is used and is the limiting reagent. In the lab, there was 1.82g of AgCl produced. What is the percent yield for this reaction?
BaCl2 + AgNO3 ---> AgCl + Ba(NO3)2
84.6% yield AgCl
500
List the names and formula of six polyatomic ions.
Ammonium NH4+
Hydroxide or alcohol OH-
Nitrate NO3-
Carbonate CO32-
Sulfate SO42-
Phosphate PO43-
500
What is the molecular shape and the hybridization of the nitrogen atom in NH3?
Trigonal pyramidal and sp3
500
500
Na2SiO3 (s) + 8 HF(aq) - --> H2SiF6 (aq) + 2 NaF(aq) + 3 H2O (l)
How many moles of HF are needed to react with 0.300 mol of Na2SiO3?
2.4mol HF
500
Given the chemical equation:
H2 + N2 ---> NH3
What is the limiting reagent give 5.0g of each of the reactants, and what is the theoretical yield?
N2 is the limiting reagent, and 12.1g is the theoretical yield.