Atomic Structure and Periodicity
What is the electron configuration of Mg2+Mg2+?
A. [Ne] 3s²
B. [He] 2s² 2p⁶
C. [Ne]
D. [Ar] 3s² 3p⁶
C. [Ne]
What is the molecular geometry of BF₃?
A. Trigonal pyramidal
B. Tetrahedral
C. Trigonal planar
D. Linear
C. Trigonal planar
How many moles are in 36.0 g of water?
A. 1.0 mol
B. 2.0 mol
C. 3.0 mol
D. 4.0 mol
B. 2.0 mol
If Q < K, which direction will the reaction shift?
A. Left
B. Right
C. At equilibrium
D. Cannot determine
B. Right
Which of the following is a strong acid?
A. HF
B. H₂CO₃
C. HCl
D. CH₃COOH
C. HCl
Which element has the highest ionization energy?
A. Na
B. Cl
C. Ar
D. K
C. Ar
Which compound exhibits hydrogen bonding?
A. CH₄
B. H₂O
C. CO₂
D. HCl
B. H₂O
What is ΔH if a reaction absorbs 250 kJ of heat and does no work?
A. ΔH = -250 kJ
B. ΔH = 0
C. ΔH = 250 kJ
D. ΔH = Cannot be determined
C. ΔH = 250 kJ
Increasing temperature shifts a exothermic reaction...
A. Right
B. Left
C. No change
D. Depends on volume
B. Left
What is the pH of a 0.001 M HCl solution?
A. 1
B. 3
C. 5
D. 7
B. 3
Which of the following ions is smallest in size?
A. O²⁻
B. F⁻
C. Na⁺
D. Mg²⁺
D. Mg²⁺
What hybridization is associated with the carbon atoms in ethyne (C₂H₂)?
A. sp
B. sp²
C. sp³
D. p only
A. sp
Which process is exothermic?
A. Melting ice
B. Condensation of steam
C. Boiling water
D. Sublimation of dry ice
B. Condensation of steam
What is the rate law for the elementary step: A+2B→CA+2B→C?
A. rate = k[A][B]²
B. rate = k[A]²[B]
C. rate = k[C]
D. rate = k[A][B]
A. rate = k[A][B]²
Which species is the oxidizing agent in: Zn+Cu2+→Zn2++CuZn+Cu2+→Zn2++Cu?
A. Zn
B. Cu
C. Cu²⁺
D. Zn²⁺
C. Cu²⁺
Which orbital is filled last for a ground-state atom of cobalt (Co)?
A. 3d
B. 4s
C. 4p
D. 3p
A. 3d
How many sigma and pi bonds are in HCN?
A. 2 sigma, 2 pi
B. 1 sigma, 3 pi
C. 3 sigma, 0 pi
D. 1 sigma, 2 pi
A. 2 sigma, 2 pi
A reaction has ΔH = -150 kJ and ΔS = -200 J/mol·K. At what temperature is it nonspontaneous?
A. Low T
B. High T
C. All T
D. Never
B. High T
The rate constant doubles when T increases from 300K to 310K. This best supports:
A. Le Châtelier’s Principle
B. Hess’s Law
C. Arrhenius Equation
D. Boyle’s Law
C. Arrhenius Equation
A buffer consists of equal moles of HF and NaF. pKa = 3.17. What is the pH?
A. 3.17
B. < 3.17
C. > 3.17
D. Cannot determine
A. 3.17
Which quantum numbers describe the 3p orbital?
A. n=3, l=1, ml=0
B. n=2, l=1, ml=2
C. n=3, l=0, ml=0
D. n=3, l=2, ml=1
A. n=3, l=1, ml=0
Which set of atoms has the most polar bond?
A. C-H
B. N-O
C. H-F
D. S-Cl
C. H-F
Use bond enthalpies to estimate ΔH for:
H2+Cl2→2HClH2+Cl2→2HCl
Bonds: H–H = 436, Cl–Cl = 242, H–Cl = 431
A. -184 kJ
B. -103 kJ
C. +184 kJ
D. +103 kJ
A. -184 kJ
For the reaction: N2O4⇌2NO2N2O4⇌2NO2, doubling volume at equilibrium will...
A. Shift left
B. Shift right
C. No shift
D. Increase pressure
B. Shift right
What is the standard cell potential for:
Zn(s)+Cu2+(aq)→Zn2+(aq)+Cu(s)Zn(s)+Cu2+(aq)→Zn2+(aq)+Cu(s)?
Given: ECu2+/Cu∘=+0.34 VECu2+/Cu∘=+0.34V, EZn2+/Zn∘=−0.76 VEZn2+/Zn∘=−0.76V
A. +1.10 V
B. -1.10 V
C. +0.42 V
D. -0.42 V
A. +1.10 V