1.) What Is the Molar Mass Of

LBS 171 REVIEW QUESTIONS

MOLAR MASS

1.) What is the molar mass of

a.) Na

b.) H2

c.) NH4

d.) C3H6Cl2

MOLARITY

2.) What is the molarity of

a.) 3.62 mol NaCl in a 400.0 mL solution

b.) 0.36 g Na3PO4●12H2O in a 200.0 mL solution

c.) HCl if 130.0 mL water is added to 20.0 mL of a 0.5 M HCl solution

STOICHIOMETRY

3.) What mass of Al(OH)3 is needed to create 6.0 mol of AlCl3 in:

Al(OH)3 + 3HCl " AlCl3 + 3H2O

4.) How many g CO2 produced from combustion of 27.4 g of C6H8 in the unbalanced

equation: C6H8 + O2 " CO2 + H2O

If 87.6 g CO2 is actually produced in an experiment, what is the percent yield of CO2?

5.) How many moles of AlCl3 are needed to completely react with the NaOH in 120.0 mL

of a 4.2 M NaOH solution in the unbalanced equation:

AlCl3 + NaOH(aq) " Al(OH)3 + NaCl

LIMITNG REACTANT

6.) What mass of CrCl3 is produced from 32.6 g Cr and 56.0 g Cl3 in:

2Cr(s) + 3Cl2(g) " 2CrCl3(s)

What mass of excess reactant is left after the reaction completes?

7.) What mass of CaSO4 is produced if 13.4 g CaCO3, 15.0 L O2 gas, and 10.0 L SO2 gas

are added in a closed system in the unbalanced equation:

SO2(g) + CaCO3(s) + O2(g) " CaSO4(s) + CO2(g)

What volume of O2 gas remains, if any, after the reaction completes?

D(O2 gas) = 1.429 g/L, D(SO2 gas) = 2.551 g/L

RYDBERG

8.) Using the Rydberg equation, find the λ of light emitted when an e- falls from n=5 to

n=2 in an H atom

ELECTROMAGNETIC RADIATION

9.) Calculate the frequency of green light with a wavelength of 540 nm. How much energy, in kJ, does 1.0 mol of photons of this light have?

10.) Rank the following types of electromagnetic radiation in order of increasing frequency: Gamma rays, Infrared rays, UV rays, Radio waves

11.) What is the wavelength of EM radiation with an Energy of 3296.1 kJ/mol?

BOHR

12.) What is the energy, in kJ/mol, of an electron in the n = 4 orbit of an H atom?

13.) Compute the minimum frequency of light required to remove an electron from the

n = 3 orbit of an H atom

14.) What are the wavelength and frequency of light emitted when an electron drops from

n = 3 to n =2 ?

QUANTUM NUMBERS

15.) a.) When n = 3, what are the possible values of l ?

b.) When l = 3, what are the possible values of ml ?

c.) For a 6d orbital, what are the possible values of n, l, and ml ?

16.) a.) How many subshells occur in the electron shell with n = 3?

b.) How many orbitals occur possible in the electron shell with n = 4?

c.) How many orbitals can be defined by l = 3?

d.) What is the maximum number of electrons in an atom that can be defined with

l = 1 ?

e.) How many nodal surfaces occur in a d subshell?

17.) Which of the following sets of quantum numbers for an electron in an atom are

Impossible?

a.) n = 1, l = 1, ml = -1

b.) n = 4, l = 0, ml = -2

c.) n = 3, l = 2, ml = 2, ms = 0

ELECTRON CONFIGURATION

18.) Write the electron configuration for the following:

a.) N

b.) Co

c.) Sr

19.) Write the noble gas shorthand for the following:

a.) Fe

b.) Cr

c.) Gd

20.) Draw an energy level diagram for Al. Is it paramagnetic or diamagnetic?

PERIODIC TRENDS

21.) Arrange the following sets of elements in order of increasing size:

a.) K, Po, Ba, Ga

b.) Zr, Cr, Cr2+, V

22.) Arrange the following sets of elements in order of increasing ionization energy:

a.) Be, K, B, N, O

b.) Na, Ca2+, Ca, Na+

LEWIS DOT STRUCTURES

23.) Draw the Lewis structures for the following compounds:

a.) N2

b.) CO2

c.) XeF4

d.) H2SO4

24.) Draw the Lewis structure and all of the resonance structures and calculate the bond

order for the following

compounds:

a.) NO2

b.) PO4

NAMING COMPOUNDS

25.) Name the following ionic compounds:

a.) NaCl

b.) CaCO3

c.) Au(OH)3

26.) Name the following molecular compounds:

a.) S2Cl2

b.) HF

27.) Name the following acids:

a.) HClO3

b.) H2CO3

c.) HCl

28.) Name for the following compounds:

a.) HIO4

b.) Sn(CN)2

c.) SrSO3

29.) Give the formula for the following compounds:

a.) ammonium chloride

b.) hydrophosphorous acid

c.) dihydrogen monoxide

MOLECULAR STRUCTURE

30.) Draw the molecular structure and give approximate bond angles for the following

compounds:

a.) CH4

b.) PCl5

c.) SF6

31.) Draw and name the molecular structure of the following compounds:

a.) H2O

b.) SF4

c.) XeF4

POLARITY

32.) Determine if the following molecules are polar:

a.) CO2 X(C) = 2.5, X(O) = 3.5

b.) CHCl3 X(C) = 2.5, X(Cl) = 3.5, X(H) = 2.1

c.) CH4

HYBRIDIZATION

33.) Draw the orbital overlaps responsible for chemical bonding in the following

Molecules:

a.) CH4

b.) C2H4

ORGANIC CHEMISTRY

34.) Draw the organic products of the following reactions

a.)

b.)

c.)

d.)

e.)

f.)

g.)

h.)

HEAT TRANSFER

35.) Calculate the heat absorbed, in kJ, when a 50.0 g block of ice at -2 °C is converted to

steam at 109°C

cs(ice) = 2.09 J/g*°C, cs(water) = 4.184 J/g*°C, cs(steam) = 2.01 J/g*°C

ΔHfus(H2O) = 6.01 kJ/mol, ΔHvap(H2O) = 40.7 kJ/mol,

36.) A 130.0 g bar of iron at 370.0 °C is immersed in 500.0 g of water at 20.0 °C. Find the

final temperature for the iron and the water.

cs(iron) = 0.444 J/g*°C cs(water) = 4.184 J/g*°C

CHANGE IN ENTHALPY

37.) Find ΔHreaction° for the combustion of ethanol.

ΔHf°(ethanol) = -277.7 kJ/mol

ΔHf°(H20) = -241.8 kJ/mol

ΔHf°(CO2) = -393.51 kJ/mol

38.) 0.140 mol NaOH and 0.030 mol HCl are reacted in 100.0 g water:

NaOH(aq) + HCl(aq) à H2O + NaCl(aq)

The water heats from 23.0°C to 26.7°C during the reaction.

Find ΔHreaction for HCl

cs(H2O) = 4.184 J/g*°C