A.P. Chemistry

First Semester review

How many grams of sodium chloride are dissolved in 50.0 mL of 1.50 M solution

A) 23.4 g

B) 0.00324 g

C) 4.38 x 103 g

D) 117 g

E) 4.38 g

Volume x Molarity = moles

1.5 minutes

In the following reaction, the oxidation numbers on sulfur are:

NaCl + H2SO4 + MnO2 ---> Na2SO4 + MnSO4 + H2O + Cl2

A  +4, +6 and +4 respectivelyB  +4, +4 and +4 respectivelyC  +6, +6 and +6 respectivelyD  +6, +6 and +4 respectivelyE  +4, +6 and +6 respectively

What is being oxidized?

1 minute

…the chlorine is being oxidized

Using the rules for significant figures, calculate the following: (8.790 - 13)/3.90

A) -1 B) -1.03C) -1.079D) -1.08E) -1.1

+ or – (to the place)

X or / (to the number of sig figs)

1 minute

Which of the following is named incorrectly? A) HClO2 : chlorous acid

B) H2SO4 : sulfuric acid C) H3PO3 : phosphorous acid D) H2CO2 : carbonous acid E) HClO : hydrochlorous acid

Hydro- prefix is used when there is no oxygen 1 minute

The element hafnium (Hf) has five stable isotopes. The correct number of nuclear particles in an atom of hafnium-178 is: A  72 protons, 72 electrons B  72 protons, 106 electrons  C  72 protons, 178 neutrons    D  106 protons, 72 neutrons   E  72 protons, 106 neutrons

Mass # = protons + neutrons

1 minute

When 13.5 grams of methane (CH4) burns in 40.0 grams of oxygen, how many grams of water are formed?

A  22.5 grams H2O    B  24.0 grams H2O       C  30.3 grams H2O        D  112 grams H2O       E  18.0 grams H2O

Oxygen in the L.R.

2.5 minutes

How big a volume of dry oxygen gas at STP would you need to take to get the same number of oxygen molecules as there are hydrogen molecules in 25.0 liters at 0.850 atm and 35°C        A  18.8 L  B  0.656 L     C  0.068 L            D  4.2 L          E  32.3 L

Ideal Gas Law

1 minute

At a temperature of 250K, the molecules of an unknown gas, Z, have an average velocity equal to that of HI at 500K. What is the identity of the gas?           A  SO2          B  N2           C  NO2           D  CO2          E  O2

urms = (3RT/MM)½

2 minutes

Calculate the work done for the expansion of oxygen gas from 2.5 liters to 3.7 liters against a pressure of 720 torr.         A  -4.78 liter·atm          B  -1.14 liter·atm           C  8.79 liter·atm           D  -864 liter·atm           E  864 liter·atm

w = -PV

1 minute

Calculate the change in enthalpy in the formation of 1 mole of PbSO4(s) from its elements, given the following:

Pb(s) + S(s) --> PbS(s) + 94 kJ/mol

PbS(s) + 2O2(g) --> PbSO4(s) + 824 kJ/mol

        A  730 kJ/mol         B  -730 kJ/mol          C  -918 kJ/mol          D  None of these          E  918 kJ/mol

Hess’s Law

1.5 minutes

Which of the following statements are true?    A.  It is harder to remove an electron from Na than from Na+.    B.  The first ionization energy of fluorine is greater than the first ionization energy of oxygen.          C  As the atomic number increases within a group of the representative elements, the tendency is for first ionization energy to increase.      D  All particles with the electron configuration [Ar]4s2 have the same ionization energy.      E  All are false

Zeff is greater for F

1.25 minutes

How many f orbitals have n = 3 (the third energy level)?   A  0          B  5       C  3         D  1        E  7

You can’t have “f” orbitals until n=4

30 s

Which of the following molecules must contain at least one double bond          A  H2O2

          B  CCl4          C  CH3I          D  CH3COOH          E  H2O

What is the name of the group –COOH?

carboxyl!!!!45 s

In which of the following compounds does the bond between the central atom and chlorine have the greatest ionic character?

        A  BCl3          B  HCl          C  FeCl2          D  CCl4           E  CaCl2

Ca is the least electronegative metal. You should know the trend for electronegativity to figure this out.

45 s

Which of the following ionic compounds has the smallest lattice energy?    A  CaCl2     B  MgS         C  Na2O         D  LiF         E  CaO

Smallest ion charges...weakest attraction. If all charges the same then the sizes make a difference. The smaller the more coulombic attraction.

45 s

Nitrogen triiodide, NI3, is an unstable molecule that is used as a contact explosive. Its molecular structure is:  A  none of these    B  octahedral      C  square planar   D  tetrahedral    E   trigonal pyramidal

45 s

Hybridization of carbon in the molecule CH2O is of the form           A  d2sp3

          B  sp2

         C  sp           D  dsp3           E  sp3

45 s

The geometry associated with d2sp3 hybridization is:       A  trigonal planar        B  octahedral          C  trigonal biplanar         D  tetrahedral           E  linear

30 s

Name this:

butane30 s

Name this:

ethene30 s

Name this:

ethanoic acid30 s