August 2009 Chemistry Regents #21-30

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Questions 1-10 Questions 11-20 Questions 21-30 Questions 31-40 Questions 41-50

Questions 51-55 Questions56-58 Questions 59-63 Question 64 Questions 65-67 Questions 68-72 Questions 73-76 Questions 77-79 Questions 80-81

 

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Questions

AnswerExplanations
21 According to the kinetic molecular theory, which statement describes the particles in a sample of an ideal gas?
(1) The force of attraction between the gas particles is strong.
(2) The motion of the gas particles is random and straight-line.
(3) The collisions between the gas particles cannot result in a transfer of energy between the particles.
(4) The separation between the gas particles is smaller than the size of the gas particles themselves.		2KMT-gas travel in straight line random motion

no attractions

molecules no volume

elastic collsions

22 The activation energy of a chemical reaction can be decreased by the addition of
(1) a catalyst       (3) electrical energy
(2) an indicator   (4) thermal energy		1definition catalyst
23 A straight-chain hydrocarbon that has only one double bond in each molecule has the general formula
(1) CnH2n-6     (3) CnH2n
(2) CnH2n-2     (4) CnH2n+2		3alkene Table Q
24 Why can an increase in temperature lead to more effective collisions between reactant particles and an increase in the rate of a chemical reaction?
(1) The activation energy of the reaction increases.
(2) The activation energy of the reaction decreases.
(3) The number of molecules with sufficient energy to react increases.
(4) The number of molecules with sufficient energy to react decreases.		3reaction = effective collisions

temperature =>molecules avg. kinetic energy

25 Which reaction results in the production of soap?
(1) esterification    (3) polymerization
(2) fermentation    (4) saponification		4saponification makes soap  fat (ester) + base==> soap and glycerol
26 Which substance is always a product when an Arrhenius acid in an aqueous solution reacts with an Arrhenius base in an aqueous solution?
(1) HBr     (3) KBr
(2) H2O    (4) KOH		2neutralization is water
27 Which substance is an electrolyte?
(1) CCl4    (3) HCl
(2) C2H6   (4) H2O		3acid base or salt

HCl is an acid

28 One acid-base theory defines a base as an
(1) H+ donor        (3) H donor
(2) H+ acceptor   (4) H acceptor		2acid H+ donor

base H+ acceptor

29 A change in the nucleus of an atom that converts the atom from one element to another element is called
(1) combustion     (3) polymerization
(2) neutralization   (4) transmutation		4definition Trans-MUTATION
2Table N

Questions 1-10 Questions 11-20 Questions 21-30 Questions 31-40 Questions 41-50

Questions 51-55 Questions56-58 Questions 59-63 Question 64 Questions 65-67 Questions 68-72 Questions 73-76 Questions 77-79 Questions 80-81

 
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