January 2008 Chemistry Regents #41-50

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

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41 A rigid cylinder with a movable piston contains a 2.0-liter sample of neon gas at STP. What is the volume of this sample when its temperature is increased to 30.°C while its pressure is decreased to 90. kilopascals?
(1) 2.5 L    (3) 1.6 L
(2) 2.0 L    (4) 0.22 L		 1 PV/T=PV/T

90(2)/303 =101.3(V)/273

P decreases and temp increases

volume should increase
42 Which compound is a saturated hydrocarbon?
(1) CH2CH2 (3) CH3CHO
(2) CH3CH3 (4) CH3CH2OH		 2 hydrocarbon C and H only

saturated, alkanes, all single bonds CnH2n+2
43 A molecule of a compound contains a total of 10 hydrogen atoms and has the general formula CnH2n+2. Which prefix is used in the name of this compound?
(1) but-     (3) oct-
(2) dec-    (4) pent-		 1 4 carbons

Table P
44 Reduction occurs at the cathode in
(1) electrolytic cells, only
(2) voltaic cells, only
(3) both electrolytic cells and voltaic cells
(4) neither electrolytic cells nor voltaic cells		 3 both, never changes

 

Red Cat An OX
45 What are the products of a reaction between KOH(aq) and HCl(aq)?
(1) H2 and KClO    (3) KH and HClO
(2) H2O and KCl    (4) KOH and HCl		 2 neutralization water and salt
46 Which volume of 0.10 M NaOH(aq) exactly neutralizes 15.0 milliliters of 0.20 M HNO3(aq)?
(1) 1.5 mL     (3) 3.0 mL
(2) 7.5 mL     (4) 30. mL		 4 MV=MV

0.20(15.0)=0.10(V)
47 Which indicator, when added to a solution, changes color from yellow to blue as the pH of the solution is changed from 5.5 to 8.0?
(1) bromcresol green (3) litmus
(2) bromthymol blue (4) methyl orange		 2 Table
4 each pH unit is 10 times the previous

acids (H+) low pH is more acidic

increases by 10
4 36.0s/7.2= 5 half lives

1/2   1/4  1/8  1/16  1/32
50 Which radioactive isotope is used in treating cancer?
(1) carbon-14      (3) lead-206
(2) cobalt-60       (4) uranium-238		 2 just has to be memorized

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