January 2014 Chemistry Regents #31-40

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

Questions 51-54 Questions 55-57 Questions 58-61 Questions 62-63 Questions 64-65 Questions 66-70

Questions 71-75 Questions 76-77 Questions 78-81 Questions 82-85

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31 Which ion has the smallest radius?

(1) O2-

(2) S2-

(3) Se2-

(4) Te2-

1 Link since they are all in the same group, the smallest is on top (fewest energy levels)

32 Equal amounts or ethanol and water are mixed at room temperature and at 101.3 kPa. Which process is used to separate ethanol from the mixture?

(1) distillation

(2) reduction

(3) filtration

(4) ionization

1 Link liquids can be separated by boiling points (distillation)

33 A sample of a substance has these characteristics:

melting point or 9811 K

hard. brittle solid at room temperature

poor conductor of heat and electricity as a solid

good conductor 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 Given the balanced equation representing reaction:

N2 + energy ==> N + N

Which statement describes this reaction?

( I) Bonds are broken, and the reaction is endothermic.

(2) Bonds are broken , and the reaction is exothermic.

(3) Bonds are formed, and the reaction  is endothermic.

(4) Bonds are formed, and the reaction  is exothermic.

1 Link breaking bonds requires energy

35 When lithium 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 charged ion

(4) loses three electrons and becomes a positively charged ion

3 Link Metals are losers of electrons and become positive

36 A beaker with water and the surrounding air are all at 24C. After ice cubes are placed in the water, heat is transferred from

(1) the ice cubes to the air

(2) the beaker to the air

(3) the water to the ice cubes

(4) the water to 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 0.50 atm

(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 container from 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.

 

2 Link Kelvin temperature and pressure are directly related

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:

Which elements 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 to a sample or a substance.

During interval AB, 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

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

Questions 51-54 Questions 55-57 Questions 58-61 Questions 62-63 Questions 64-65 Questions 66-70

Questions 71-75 Questions 76-77 Questions 78-81 Questions 82-85

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