August 2007 Chemistry Regents #21-30

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

Other Regents Exams

Questions	Answer	Explanations
21 Given the balanced equation representing a reaction: Cl2(g) ==> Cl(g) + Cl(g) What occurs during this change? (1) Energy is absorbed and a bond is broken. (2) Energy is absorbed and a bond is formed. (3) Energy is released and a bond is broken. (4) Energy is released and a bond is formed.	1	a bond was broken, the atoms are separated energy is absorbed
22 A molecule of butane and a molecule of 2-butene both have the same total number of (1) carbon atoms      (3) single bonds (2) hydrogen atoms   (4) double bonds	1	but- 4 carbons
23 Which general formula represents the homologous series of hydrocarbons that includes the compound l-heptyne? (1) CnH2n–6 (3) CnH2n (2) CnH2n–2 (4) CnH2n+2	2	yne= alkynes table Q
24 Which two compounds are isomers of each other? (1) CH3CH2COOH and CH3COOCH2CH3 (2) CH3CH2CHO and CH3COCH3 (3) CH3CHBrCH3 and CH2BrCHBrCH3 (4) CH3CHOHCH3 and CH3CHOHCH2OH	2	same formula different structures count atoms
	2	unsaturated (contains a double or triple bond) hydrocarbon carbon and hydrogen only
26 Which formula represents a hydronium ion? (1) H3O+ (3) OH– (2) NH4+ (4) HCO3–	1	Table E
27 Which compound is an Arrhenius acid? (1) H2SO4     (3) NaOH (2) KCl         (4) NH3	1	starts with H
	2	Table N
29 Which nuclear emission has the greatest penetrating power? (1) alpha particle   (3) gamma radiation (2) beta particle    (4) positron	3	most gamma, beta, alpha least
30 What is the mass number of an alpha particle? (1) 1    (3) 0 (2) 2    (4) 4	4	table O, top number