January 2014 Chemistry Regents #31-40
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Other Regents Exams
31Which ion has the smallest radius?
|1||Link||since they are all in the same group, the smallest is on top (fewest energy levels)|
32 Equal amounts or ethanol andwater are mixed at room temperature and at 101.3 kPa. Which process is used to separate ethanol from the mixture?
|1||Link||liquids can be separated by boiling points (distillation)|
33 A sample of a substance has these characteristics:
• meltingpoint or 9811 K
• hard. brittle solid at room temperature
• poor conductor of heat and electricity asa solid
• goodconductor of electricity as a liquid or in an aqueous solution
This sample is classified as
(1)a metallic element
(2) a radioactive element
(3) a molecular compound
(4) an ionic compound
|4||Link||properties of an ionic compound|
34 Giventhe balanced equation representing reaction:
N2+ energy ==> N + N
Whichstatement describes this reaction?
( I) Bonds are broken, and the reactionis endothermic.
(2) Bonds are broken , and the reaction is exothermic.
(3)Bonds are formed, and the reaction is endothermic.
(4) Bonds areformed, and the reaction is exothermic.
|1||Link||breaking bonds requires energy|
35 Whenlithium reacts with bromine to form the compound LiBr each lithium atom
(1) gains one electron and becomes a negatively charged ion
(2) gains three electrons and becomes a negatively charged ion
(3) loses one electron and becomes a positively chargedion
(4) loses three electrons and becomes a positively charged ion
|3||Link||Metals are losers of electrons and become positive|
36 A beaker withwater and the surrounding air are all at 24°C. After ice cubes are placed in the water, heat is transferred from
(1) the ice cubes to the air
(2) the beaker tothe air
(3)the water to the ice cubes
(4) the waterto the beaker
|3||Link||heat transfers from hot to cold, so water to ice cube|
37 A sample of chlorine gas is at 300. K and 1.00 atmosphere.At which temperature and pressure would the sample be have more like an ideal gas?
(1) 0 K and 1.00 atm
(2) 150. K and 0.50atm
(3) 273 K and .1.00 atm
(4) 600. K and 0 .50 atm
|4||Link||high temperature and low pressures
are ideal conditions for a gas
Like an ideal vacation
38 When a sample of a gas is heated in a sealed, rigid containerfrom 200. K to 400. K, the pressure exerted by the gas is
(1) decreased by a factor of 2.
(2)increased by a factor of 2.
(3) decreased by a factor of 200.
(4)increased by a factor of 200.
Kelvin temperature and pressure are directly
Kelvin temp doubles so does pressure
|39 The bright- line spectra
produced by four elements are represented ill the diagram below.
Given the bright- line spectrum or a mixture formed from two or these elements:
Whichelements are present in this mixture?
( I) A and D (3)Z and D
(2) Aand X (4) Z and X
|1||Link||all the lines of the element must be in the unknown|
40 The graph below represents the relation ship between time and temperature as heal is added at a constant rate toa sample or a substance.
During intervalAB, which energy change occurs for the particles in this sample?
( l ) The potential energy or the particles increases.
(2) The potential energy or the particles decreases.
(3) The average kinetic energy of the particles increases.
(4) The average kinetic energy or the particles decreases.
|1||Link||plateaus, phase changes, potential energy changes|
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