Sanjac CHEM1311 test 2 LATEST 2022

How many grams of Li3N can be formed from 1.75 moles of Li? Assume an excess of nitrogen.

 6 Li(s) +N2(g)  ->  2 Li3N(s)

A 18.3 g Li3N

B 20.3 g Li3N

C 58.3 g Li3N

D 61.0 g Li3N

How many moles of oxygen are formed when 58.6 g of KNO3 decomposes according to the following reaction?  The  molar mass of KNO3 is 101.11 g/mol.

  4 KNO3(s)  ->  2 K2O(s) + 2 N2(g)+ 5 O2(g)

A 0.290 mol O2

B 0.580 mol O2

C 18.5 mol O2

D 0.724 mol O2

Consider the following balanced reaction.  How many grams of water are required to form 75.9 g of HNO3?  Assume that there is excess NO2 present.  The molar masses are as follows:  H2O = 18.02 g/mol, HNO3 = 63.02 g/mol.

  3 NO2(g)+ H2O(l)  ->  2 HNO3(aq)+ NO(g)

A 38.0 g H2O

B 21.7 g H2O

C 43.4 g H2O

D 10.9 g H2O

4. Determine the limiting reactant (LR) and the mass (in g) of nitrogen that can be formed from 50.0 g N2O4 and 45.0 g N2H4.  Some possibly useful molar masses are as follows:  N2O4 = 92.02 g/mol, N2H4= 32.05 g/mol.

   N2O4(l)+ 2 N2H4(l) ->  3 N2(g)+ 4 H2O(g)

A LR = N2H4,59.0 g N2 formed

B LR = N2O4,105 g N2 formed

C LR = N2O4, 45.7 g N2 formed

D  LR = N2H4, 13.3 g N2 formed

Determine the theoretical yield of HCl if 60.0 g of BCl3 and 37.5 g of H2Oare reacted according to the following balanced reaction.  A possibly useful molar mass is BCl3= 117.16 g/mol.

BCl3(g) + 3 H2O(l)  ->  H3BO3(s) + 3 HCl(g)

A 75.9 g HCl

B 132 g HCl

C 187 g HCl

D 56.0 g HCl

Determine the percent yield of a reaction that produces 28.65 g of Fe when 50.00 g of Fe2O3 react with excess Al according to the following reaction.

  Fe2O3(s)+ 2 Al(s)  ->  Al2O3(s)+ 2 Fe(s)

A 61.03%

B 28.65%

C 57.30%

D 81.93%

 

Determine the molarity of a solution formed by dissolving  4.00moles of KBr in enough water to yield 3.00 L of solution.

A 1.33 M

B 2.00 M

C .750 M

D 3.00 M

Determine the molarity of a solution formed by dissolving 97.7 g  LiBr in enough water to yield 750.0 mL of solution.

A 1.50 M

B 1.18 M

C 0.130 M

D 0.768M

Choose the statement below which is TRUE,

A a weak acid solution consists of mostly nonionized acid molecules

B the term "strong electrolyte" means that the substance is extremely reactive

C a strong acid solution consists of only partially ionized acid molecules

D the term "weak electrolyte" means that the substance is inert

Give the complete ionic equation for the reaction (if any) that occurs when aqueous solutions of lithium sulfide and copper(II) nitrate are mixed.

A2 Li+(aq) + S2–(aq) + Cu2+(aq) + 2 NO3–(aq)  ®  Cu2+(aq) + S2–(aq)+ 2 Li+(aq) + 2 NO3–(aq)

B 2 Li+(aq)+ S2–(aq) + Cu2+(aq) + 2 NO3–(aq)  ®  CuS(s) + 2 LiNO3(s)

C 2 Li+(aq)+ S2–(aq) + Cu2+(aq) + 2 NO3–(aq)  ®  Cu2+(aq) + S2–(aq)+ 2 LiNO3(s)

D 2 Li+(aq) + S2–(aq) + Cu2+(aq) + 2 NO3–(aq)  ®  CuS(s) + 2 Li+(aq)+ 2 NO3–(aq)

Give the net ionic equation for the reaction (if any) that occurs when aqueous solutions of K2S and Fe(NO3)2 are mixed.

A K+(aq) + NO3–(aq)  ->  KNO3(s)

B Fe2+(aq) + S2–(aq) + 2 K+(aq) + 2 NO3–(aq)  ->  FeS(s) + 2 K+(aq) + 2 NO3–(aq)

C  Fe2+(aq) + S2–(aq) + 2 K+(aq)+ 2 NO3–(aq) ->  Fe2+(aq) + S2–(aq) + 2KNO3(s)

D Fe2+(aq) + S2–(aq)  ->  FeS(s)

Define an Arrehenius acid

A an electron pair donor

B an electron pair receiver

C produces H+ in aqueous solution

D accepts H+ ions

 Identify the combustion reaction

A 2 C3H7OH(l)+ 9 O2(g)  ->  6 CO2(g) + 8 H2O(g)

B 2 H2(g) + O2(g)  ->  2 H2O(g)

CC3H8(g) + 5 O2(g)->  3 CO2(g) + 4 H2O

D All of the reactions are examples of combustion reactions.

Determine the oxidation state of P in PO33-

A+3

B+6

C+2

D0

What element is undergoing reduction (if any) in the following reaction?

    Zn(s) + 2 AgNO3(aq)  ->  Zn(NO3)2(aq)+ 2 Ag(s)

A Zn

B N

C O

D Ag

Identify the species reduced.

   2 Al3+(aq) + 2 Fe(s)  ->  2 Al(s) + 3 Fe2+(aq)

A Al3+

B Fe

C Al

D Fe2+

What volume (in mL) of 0.0887 M MgCl2 solution is needed to make 275.0 mL of 0.0224 M MgCl2solution?

A 72.3 ml

B 91.8 ml

C 10.9 ml

D 69.4 ml

Define pressure

A force used to compress a gas

B force applied to a gas to compress it

C force exerted per unit area by gas particles as they strike the surfaces around them

D force applied by a solid to the surrounding area

 An instrument used to measure atmospheric pressure is called a

A barometer

Bmanometer

Csphygmomanometer

Dspectrophotometer

an instrument used to measure blood pressure is called a

Abarometer

Bmanometer

Csphygmomanometer

Dspectrophotometer

The volume of a gas is proportional to the temperature of a gas is known as

Aavagadro's law

Bideal gas law

Ccharles's law

Dboyles's law

The volume of a gas is proportional to number of moles of a gas is known as

Aavogadro's law

Bideal gas law

Ccharles's law

Dboyle's law

The volume of a gas is inversely proportional to the pressure of a gas is known as

Aavogadro's law

Bideal gas law

Ccharles's law

Dboyle's law

A child receives a helium balloon in a shopping mall.  When he goes outside during a snowstorm, the balloon decreases in size.  Which gas law is this an example of?

Aavogadro's law

Bideal gas law

Ccharles's law

Dboyles's law

To what temperature must a balloon, initially at 25°C and 2.00 L, be heated in order to have a volume of 6.00 L?

A993 K

B403 K

C75K

D894 K

What pressure will 14.0 g of CO exert in a 3.5 L container at 75°C?

A4.1 atm

B5.0 atm

C6.4 atm

D1.1 atm

What is the volume of 5.60 g of O2 at 7.78 atm and 415 K?

A1.53 L

B565 L

C24.5 L

D0.766 L

A 0.465 g sample of an unknown compound occupies 245 mL at 298 K and 1.22 atm.  What is the molar mass of the unknown

compound?

A26.3 g/mol

B33.9 g/mol

C12.2 g/mol

D38.0 g/mol

The total pressure of a gas mixture is the sum of the partial pressure of its components is known as

Aavogadro's law

Bdalton's law

Ccharles's law

Dboyles's law

Determine the theoretical yield and the percent yield if 21.8 g of K2CO3 is produced from reacting 27.9 g KO2 with 29.0 L of CO2 (at STP).  The molar mass of KO2 = 71.10 g/mol and K2CO3 = 138.21 g/mol.

 4 KO2(s) + 2 CO2(g)  ->  2 K2CO3(s) + 3 O2(g)

A

27.1 g, 80.4% yield

B

179 g, 12.2% yield

C

91.7 g, 23.8% yield

D

206 g, 10.6% yield

Which statement is TRUE about the kinetic molecular theory?

Aa single particle does not move in a straight line

Bthe size of the particle is large compared to the volume

Cthe collisions of particles with one another is completely elastic

Dthe average kinetic energy of a particle is not proportional to temperature

The rate of effusion of two different gases is known as

Aavogadro's law

Bgraham's law

Ccharles's law

Dboyle's law

Give the definition for diffusion

Agas molecules mix equally

Bgas molecules spread out in response to a concentration gradient

Cgas molecules escape from a container into a vacuum through a small hole

Daverage distance between collisions

Define mean free path

Aaverage distance that a molecule travels between collisions

Bdiameter of a molecule

Cdistance between molecules in a gas

Dtime for effusion

This equation is used to calculate the properties of a gas under nonideal conditions

Acharles's law

Bavogadro's law

Cboyles's law

D van der Waals equation