January 2012 Chemistry Regents #21-30

Highlight to reveal answers and explanations

 

Questions 1-10 Questions 11-20 Questions 21-30 Questions 31-40 Questions 41-50 Questions 51-54 Questions 55-57 Questions 58-59 Questions 60-62 Questions 63-65 Questions 66-69  Questions 70-71  Questions 72-74 Questions 75-78  Questions 79-81  Questions 82-85

 

Other Regents Exams

Questions

AnswerLinkExplanations

21 Which element has the lowest electronegativity value?

(1) F     (2) Fr     (3) Cl     (4) Cr

2link 

Table S has the values

22 At standard pressure, CH4 boils at 112 K and H2O boils at 373 K. What accounts for the higher boiling point of H2O at standard pressure?

(1) covalent bonding    (3) hydrogen bonding

(2) ionic bonding         (4) metallic bonding

3link 

water's IMF are hydrogen bonding, while CH4's are van der Waals forces (London)

23 A mixture of sand and table salt can be separated  by filtration because the substances in the  mixture differ in

( I) boiling point      (2) density at STP

(3) freezing point     (4) solubility in water

4link 

sand is insoluble in water

24 Systems in nature toward  tend to undergo changes

(1) lower energy and lower entropy

(2) lower energy and higher entropy

(3) higher energy and lower entropy

(4) higher energy and higher entropy

2link

 

systems are looking for lower energy and more randomness, like your room

25 In the wave-mechanical model of the atom, an orbital is the most probable location of

(1) a proton      (3) a neutron

(2) a positron    (4) an electron

4link 

orbitals are where electrons reside

26 Functional groups are used to classify

(1) organic compounds

(2) inorganic compounds

(3) heterogeneous mixtures

(4) homogeneous mixtures

1no linkTable R

27 Which class of compounds contains at least one element from Group 17 of the Periodic Table?

(1) aldehyde    (3) ester

(2) amine        (4) halide

4link 

halogens (group 17) when bonded are called halides

28 In a propanal molecule, an oxygen atom is bonded with a carbon atom. What is the total number of pairs of electrons shared between these atoms?

(1) 1      (2) 2     (3) 3     (4) 4

2link

 

Table R has that molecule

The O is double bonded, so there are 2 pairs of shared electrons between C and O

29 When a voltaic cell operates, ions move through the

(1) anode     (2) cathode     (3) salt bridge     (4) external circuit

3link 

salt bridge= ion flow

30 When dissolved in water, an Arrhenius base yields

(1) hydrogen ions           (2) hydronium ions

(3) hydroxide ions          (4) oxide ions

4link 

Base- OH-  called hydroxide

Questions 1-10 Questions 11-20 Questions 21-30 Questions 31-40 Questions 41-50 Questions 51-54 Questions 55-57 Questions 58-59 Questions 60-62 Questions 63-65 Questions 66-69  Questions 70-71  Questions 72-74 Questions 75-78  Questions 79-81  Questions 82-85
 
Back to Regents Exams