#1
Which element is classified as a metalloid?
(1) Cr (2) Sc (3) Cs (4) Si
(4) Si
Systems in nature tend to undergo changes toward
(1) lower energy and lower entropy
(2) lower energy and higher entropy
(3) higher energy and lower entropy
(4) higher energy and higher entropy
(2) lower energy and higher entropy
Which formula can represent an alkyne?
(1) C2H4 (2) C3H4 (3) C2H6 (4) C3H6
(2) C3H4
Which electron configuration represents a potassium atom in an excited state?
(1) 2-7-6 (2) 2-8-8-1 (3) 2-8-5 (4) 2-8-7-2
(4) 2-8-7-2
Which equation represents a reduction halfreaction?
(1) Fe → Fe3 3e– (3) Fe3 → Fe 3e–
(2) Fe 3e → Fe3 (4) Fe3 3e → Fe
(4) Fe3 3e → Fe
Mg(s) 2HCl(aq) → MgCl2(aq) H2
Which type of chemical reaction is represented by the equation?
(1) synthesis
(2) decomposition
(3) single replacement
(4) double replacement
(3) single replacement
Which sample of matter has a crystal structure?
(1) Hg(ℓ) (2) NaCl(s) (3) H2O(ℓ) (4) CH4(g)
(2) NaCl(s)
Which substance can not be broken down by a chemical change?
(1) butanal (2) gold (3) propene (4) water
(2) gold
Which compound is an electrolyte?
(1) H2O (2) H3PO4 (3) C2H6 (4) CH3OH
(2) H3PO4
Which list of elements is arranged in order of increasing electronegativity?
(1) Be, Mg, Ca (3) K, Ca, Sc
(2) F, Cl, Br (4) Li, Na, K
(3) K, Ca, Sc
Which electron configuration represents an excited state for an atom of calcium?
(1) 2-8-7-1 (3) 2-8-7-3
(2) 2-8-7-2 (4) 2-8-8-2
(3) 2-8-7-3
What is the empirical formula for C6H12?
CH2
State the physical property that makes it possible to separate a solution by distillation.
boiling point/boiling temperature
What occurs when Cr3 ions are reduced to Cr2 ions?
(1) Electrons are lost and the oxidation number of chromium increases.
(2) Electrons are lost and the oxidation number of chromium decreases.
(3) Electrons are gained and the oxidation number of chromium increases.
(4) Electrons are gained and the oxidation number of chromium decreases.
(4) Electrons are gained and the oxidation number of chromium decreases.
Systems in nature tend to undergo changes that result in
(1) lower energy and lower entropy
(2) lower energy and higher entropy
(3) higher energy and lower entropy
(4) higher energy and higher entropy
(2) lower energy and higher entropy
The formula mass of a compound is the
(1) sum of the atomic masses of its atoms
(2) sum of the atomic numbers of its atoms
(3) product of the atomic masses of its atoms
(4) product of the atomic numbers of its atoms
(1) sum of the atomic masses of its atoms
Zn(s) HgO(s) → ZnO(s) + Hg(ℓ)
Determine the change in the oxidation number of zinc during the operation of the cell.
From 0 to 2
Which formula represents a polar molecule?
(1) O2 (3) NH3
(2) CO2 (4) CH4
(3) NH3
Which element is least likely to undergo a chemical reaction?
(1) lithium (3) fluorine
(2) carbon (4) neon
(4) neon
Which radioisotope has the fastest rate of decay?
(1) 14C (3) 53Fe
(2) 37Ca (4) 42K
(2) 37Ca
C4H10 Cl2 → C4H9Cl HCl
Which type of reaction is represented by the equation?
(1) addition (3) fermentation
(2) substitution (4) polymerization
(2) substitution
What is the molarity of 0.50 liter of an aqueous solution that contains 0.20 mole of NaOH (gram-formula mass = 40. g/mol)?
(1) 0.10 M (3) 2.5 M
(2) 0.20 M (4) 0.40 M
(4) 0.40 M
The three nuclides, U-233, U-235, and U-238, are isotopes of uranium because they have the same number of protons per atom and
(1) the same number of electrons per atom
(2) the same number of neutrons per atom
(3) a different number of electrons per atom
(4) a different number of neutrons per atom
(4) a different number of neutrons per atom
Which statement describes an electrolyte?
(1) An electrolyte conducts an electric current as a solid and dissolves in water.
(2) An electrolyte conducts an electric current as a solid and does not dissolve in water.
(3) When an electrolyte dissolves in water, the resulting solution conducts an electric current.
(4) When an electrolyte dissolves in water, the resulting solution does not conduct an electric current.
(3) When an electrolyte dissolves in water, the resulting solution conducts an electric current.
An alcohol and an ether have the same molecular formula, C2H6O. These two compounds have
(1) the same functional group and the same physical and chemical properties
(2) the same functional group and different physical and chemical properties
(3) different functional groups and the same physical and chemical properties
(4) different functional groups and different physical and chemical properties
(4) different functional groups and different physical and chemical properties