In what respect does an atom of magnesium differ from a magnesium ion (Mg2+)?
(A)The ion has a more stable electronic arrangement than the atom.
(B)The positive charge on the nucleus of the ion is two units greater than the nuclear charge on the atom.
(C)The ion has two more protons than the atom.
(D)The ion will react more readily with free Cl2.
(E)The ion has two more planetary electrons than the atom.
A
100
How many atoms are in 28.00 g of Carbon?
(1 mole of carbon = 12.01 g)
1.404 E+24
100
All are examples of Lewis acid–base reactions except
(A) Cu2+(aq) + 4NH3(aq) →← [Cu(NH3)4]2+(aq)
(B) HCl(g) + NH3(g) → NH4Cl(s)
(C) H+(aq) + OH–(aq) →← H2O(l)
(D) 2Na(s) + Cl2(g) → 2NaCl(s)
D
100
Which instrument is used to measure the gain or loss of heat?
(A)manometer
(B)hydrometer
(C)calorimeter
(D)barometer
(E)voltmeter
(C)calorimeter
100
E = hν
Where E is energy, ν is frequency, and h is Plank’s constant (6.626x10-34 m2kg/s)
According to equation 2, would a high frequency wave or low frequency wave have more energy?
High frequency = high energy
200
An sp hybridized central atom can be used to describe the bonding in
(A) CH4 (B) HCN (C) H2CO (D) OF2
B) HCN
200
A coulomb is defined as what?
The charge on one mole of electrons
200
All are potential Lewis bases except
(A) NH3 (B) H2O (C) CH4 (D) CN–
C) CH4
200
Which procedure will lower the activation energy for a particular reaction?
(A) subdividing the reactants
(B) increasing the reactant concentrations
(C) increasing the temperature
(D) adding a catalyst
(D) adding a catalyst
200
Oxygen and ozone have the formulas O2 and O3 respectively. They are
(A) isomers. (B) isobars. (C) allotropes. (D) isotopes.
(C) allotropes.
300
Which pair of elements is most likely to react to form a covalently bonded species?
(A) P and O (B) Ca and O (C) K and S (D) Zn and C
A) P and O
300
When equal volumes of 0.1 M solutions of HCl and NaOH are mixed, the total number of ions
present will be approximately
(A) twice as great as before mixing. (B) the same as before mixing.
(C) half as great as before mixing. (D) 10–7 times as great as before mixing.
(E) 10–14 times as great as before mixing.
(C) half as great as before mixing.
300
21. Which is a proper description of chemical equilibrium?
(A)The frequencies of reactant and of product collisions are identical.
(B)The concentrations of products and reactants are identical.
(C)The velocities of product and reactant molecules are identical.
(D)Reactant molecules are forming products as fast as product molecules are reacting to form reactants.
(E)The numbers of moles of reactants and products are equal.
(D)Reactant molecules are forming products as fast as product molecules are reacting to form reactants.
300
Which molecule has the greatest bond energy?
(A) H—Br
(B) H—F
(C) H—At
(D) H—Cl
(E) H—I
(B) H—F
300
The molecule N2 is isoelectronic with
(A)formaldehyde, CH2O
(B)cyanide ion, CN–
(C)hydrogen, H2
(D)water, H2O
(B)cyanide ion, CN–
400
Which compound would be expected to have the largest dipole moment?
(A)CO2 (linear) (B)SO2 (bent) (C)BF3 (trigonal planar) (D)CF4 (tetrahedral)
B
400
A sample of nitrogen at pressure P is contained in a sealed syringe with a movable piston. If the
volume of the sample were doubled and the absolute temperature tripled, the new pressure of the gas
would be (A) 6.0 P (B) 5.0 P (C) 3.5 P (D) 1.5 P
(D) 1.5 P
400
Which hydrated metal ion is most acidic under conditions of equal molar concentration in water?
(A) Al 3+ (B) Ba 2+ (C) K + (D) Zn 2+ (E) Ag +
A
400
Which is not a characteristic of ionic substances?
(A) Their reactions are generally extremely slow.
(B) They conduct an electric current when fused.
(C) Those having a common ion exhibit some similar chemical properties.
(D) They lower the vapor pressure of water when dissolved in it.
(E) They raise the boiling point of water when dissolved in it.
(A) Their reactions are generally extremely slow.
400
In the reaction, Zn(s) + CuSO4(aq) → ZnSO4(aq) + Cu(s),
(A) metallic zinc is the reducing agent.
(B) metallic zinc in reduced.
(C) copper ion is oxidized.
(D) sulfate ion is the oxidizing agent.
(A) metallic zinc is the reducing agent.
500
In which pair of compounds should the first member be more covalent than the second member?
(A) TlCl, TlCl3 (B) SnI4, SnF4 (C) LiF, BF3 (D) SnF4, CF4
B) SnI4, SnF4
500
An amino acid has a molar mass of 776.9 g·mol–1 and contains 65.34% iodine by mass. What is the
number of iodine atoms per molecule of amino acid?
(molar mass of iodine = 126.9 g)
(A) one (B) three (C) four (D) five
(C) four
500
When equilibrium has been reached in the reaction
AE + CD ←→ CE + AD + x kJ
in which all substances are in solution,
(A) adding AE will increase the concentration of CE but not of AD.
(B) adding CD will increase the concentration of both AE and AD.
(C) heating will increase the concentration of both AE and CE.
(D) escape of some AD by volatilization will increase the concentration of CE.
(E) doubling the pressure will increase the concentration of CE.
(D) escape of some AD by volatilization will increase the concentration of CE.
500
Which reaction has the largest positive entropy change per mole of product formed?
(A) S(s) + 3F2(g) → SF6(g)
(B) SO2(g) + Na2O(s) → Na2SO3(s)
(C) Fe 3+(aq) + SCN–(aq) → FeSCN 2+(aq)
(D) H2O(l) → H2O(g)
(D) H2O(l) → H2O(g)
500
Which of these isoelectronic ions is the smallest?
(A) O 2–
(B) F –
(C) Na +
(D) Mg 2+
(E) Al 3+