ARMY PUBLIC SCHOOL AND COLLEGE KOHAT CHEMISTRY – HSSC 1 ALL CHAPTERS MCQS AND SHORT QUESTIONS
1)
2)
When When an an elec electr tron on is is add added ed to to a uni unipo posi siti tive ve ion ion we get get (a)anion (b) cation (c)neutral atom (d) molecule CO+ is an example of: (a)free radical (c) an ionic molecular ion
(b)cationic molecular ion (d)stable molecule
) !orm !o rmula ula that that gives gives us us infor informa matio tion n about about the simple simplest st rat ratio io of atoms atoms in in compound (a) structural formula (b) mo molecular formula (c) empirical formula (d) molar ratio ")
#erc ercent entage of ox ox$ge $gen in in %2 %2O is is (a) &' (c) &&
(b) &&& (d) *&
)
When When ''1 ''1 ,g of of CaCO CaCO is deco decompo mposed sed the CO2 produ produced ced occupi occupies es a volume at -.# (a) 22"1" dm (b) 22"1" dm (c) 22"1" dm (d) 22"'1" dm
/)
.he no no of of cova covalen lentt bond bond in in 1'g 1'gm m of of 0% 0% ar are (a)/'22 x 1'2 (b) 1'/2 x 1'2 (c)1'/2 x 1'2" (d) 1'/2 x 1'2"
)
0o 0o of molec molecule ules s prese present nt in in 1'gm 1'gm of of water water are are (a) x 1'2 (b) x 1'2 (c) x 1'2" (d) x 1'2"
&)
.he no no of of covale covalent nt bonds bonds pre prese sent nt in 1'gm 1'gm of of water water are are (a) /'" x 1'2 (b)/" x 1'2 (c) /'" x 1'2" (d) /" x 1'2"
*)
'' '' cm cm of %2 %2 gas gas at -.# -.# cont contra radic dictio tions ns of of h$dr h$droge ogen n (a)/'2 x 1'2 (b)'1 x 1'22 (c)2/& x 1'22 (d)1" x 1'22
1') .he number number of moles moles of CO2 which contains &' gm of ox$gen ox$gen (a)'2 (b) '' (c)1' (d)1' 11) 2 grams of l will react react completel$ completel$ with how much much mass of of O2 to produce l2O (a)& gm of ox$gen (b)1/ gm of ox$gen (c)2 gm of ox$gen (d) 2" gm of ox$gen 12) 12)
.he .he mas mass s of of one one mole mole of elec electr tron on is (a)1''& mg
(b) '1&" mg
(c)1/ mg 1) 1)
(d) ' mg
.he .he vol volum ume e occ occup upie ied d b$ 1" 1" gm gm of of 02 02 at at -.# -.# is (a)22" dm (b) 22" dm (c)112 dm (d) 112 cm
1") .he orde orderr of the rate rate of of di3usion di3usion of gases gases 0%4 0%4 -O24 -O24 Cl2 and and CO2 is (a) 0% 5 -O2 5 Cl2 5 CO2 (b) 0% 5 CO2 5 -O2 5 Cl2 (c) Cl25 -O2 5 CO2 5 0% (d) 0one of these 1+) 6f absolute . of a gas is doubled and the pressure pressure is reduced to one half the volume of gas (a) remain unchanged (b)increases four times (c) reduce to half (d)be double
1/) t high temperature isotherm moves awa$ from both the axis because of increase in4 (a) pressure (b)volume (c) no of moles (d)all above 1)
7alues of Charle8s law constant 9 depends upon (a) mass of gas (b)pressure gas (c)no of moles of gas (d)all above
1&) ;ual volumes of %2 and %e are inserted in the the same vessel .he # exerted are in the ratio: (a) 1:1 (b) 2:1 (c) 1:2 (d) all above 1*) 6f absolute absolute temperature temperature is doubled and and the pressure pressure is increased " times times .he volume is (a) half (b) double (c) four times (d) remains the changed
2')
21)
>nits of gas constant ? in -6 s$stem is: (a) ' ''&21 dm atm ,=1 mol=1 (c) &1 0m ,=1 mol=1 mol= 1
(b) &21 cm atm ,=1 (d)1*& (d) 1*& cal ,=1 mol=1 mol= 1
22) Concept of distribution of velocities among the gas molecules was developed b$ (a)Claudius (b)@axwell (c)AoltBman (d)7anderwaal 2)
real gas obe$ing 7ander 7ander Waal8s Waal8s e;uation will resemble resemble ideal gas if: (a) both a8 and b8 are large (b) both a8 and b8 are small (c) a8 is small and b8 is large (d)a8 is large and b8 is small
2")
2)
6n Bero order reaction4 the rate is independent independe nt of (a) temperature of reaction b) concentration of reactants (c)concentration of products (d)none of above
2/)
.he rate of reaction (a)increases as the reaction proceeds reaction proceeds (c)r c)remain mains s th the sa same as th the rea reac ctio tion pr proce oceeds increase
(b) decreases as the (d)m (d)ma a$ de decrea crease se or
2)
.he unit of the rate constant is the same as that of the rate of reaction in (a)Drst order reaction (b) second order reaction (c)Bero order reaction (d) third order reaction
2&)
.he unit of reaction is (a)moleEdm (c)moleEdm sec
(b) moleEpound (d) moleEcm
2*)
.he rate of react reaction ion between between two speciDc speciDc time time intervals intervals is called called (a)instantaneous rate (b) average rate (c)speciDc rate (d) ordinar$ rate
')
.he sum of of expone exponents nts of of the conc terms terms in the rate rate e;uat e;uation ion is called called (a)rate of reaction (b) order of reaction (c)speciDc rate constant (d) average rate
1)
.he average average rate and insta instantan ntaneous eous rate of a react reaction ion are are e;ual e;ual (a)at the start (b) at the end (c)in the middle (d) when 2 rate have time interval F
Bero 2)
#hotochemical reactions usuall$ have order (a)one (b) Bero (c)two (d) three
) )
.he .he deco decomp mpos osit itio ion n of oBon oBone e has has ord order er (a)Drst (b) negative (c)second (d) pseudo Drst order
")
When a react reaction ion occurs occurs in man$ man$ steps steps then the slowe slowest st step step is the the (a)main step (b) enthalp$ determining step (c)mechanism determining step (d)rate determining step
)
.he substance which which retard the rate of chemical reaction reaction (a)catal$st (b) inhibitor (c)auto catal$st (d) enB$me
/)
.he factors which a3ect rate of reaction (a)nature of reactants (b) surface area (c)light (d) all of above
) lectrol$sis is the process in which a chemical reaction ta,es place at the expense of (a) chemical energ$ (b) electrical energ$ (c) heat energ$ (d) none of these
&)
.he oxidation number of chromium in 92Cr2O is (a)1" (b) 12 (c)/ (d) none of these
*)
6n the reaction 2 !e + Cl 2 ( 2!eCl (a) !e is reduced (c) Cl2 is oxidiBed
(b) !e is oxidiBed (d) none of these
"')
When a;ueous solution of 0aCl is electrol$sed (a) Cl2 is evolved at the cathode (b) %2 is evolved at cathode (c) 0a is deposited at the cathode (d) 0a appears appear s at the anode
"1)
Which one one of of the following will be good good conductor of electricit$ (a) pure distilled water (b) molten 0aCl (c) dilute solution of glucose (d) chloroform
"2)
")
oxidiBing agent is a substance which brings about (a) electron donation (b) oxidation (c) reduction (d) h$drol$sis
"")
6n the electrol$sis the process of oxidation occurs at (a) anode (b) cathode (c) both cathode and anode (d) in electrol$tic electrol$tic solution
")
6n an oxidation process the oxidation number of the element (a) increases (b) decreases (c) does not change (d) 0one
"/)
Oxidation number of ox$gen in O!2 is (a) + 1 (b) = 1 (c) + 2 (d) G 2
") substance which in molten state or in solution form form allows electric current to pass is (a) electrol$te electrol$te (b) insulator (c) conduction (d) none of these "&) called
n apparatus apparatus in which which chemical chemical energ$ energ$ in converted to electrical energ$ is (a) electrol$tic cell (c) fuel cell
"*)
(b) galvanic cell (d) down cell
-odium metal is obtained b$ the electrol$sis electrol$sis of fused 0aCl in a cell is called (a) 0elson8s cell (b)
') .he change in heat energ$ of a chemical reaction at constant temperature and pressure is (a)enthalp$ change (b) bond energ$ (c)heat of sublimation (d) internal energ$ change 1)
Calorie is e;uivalent to
2)
(a)'"1&" H (c)"1&" H
(b) "1&" H (d) "1&" H
.he unit of enthalp$ change is (a)calorie (c)volt
(b) Ioule (d) coulomb
)
.he freeBing mixture mixture used in ice cream machine consists of ice and (a)0aCl (b) CaCl2 (c)90O (d) both a J c
")
.he term cr$oscop$ is used (a)depression of freeBing point (c)lowering of of va vapour pressure
(b)ele )elevation in boiling point (d) os osmotic pr pressure
.he term ebullioscop$ is used (a)depression of of fr freeBing po point (c)lower of vapour pressure
(b) elevation in in bo boiling po point (d) no none of above
)
/)
Which one of following is not a conIugate solution (a)ether + water (b) phenol + water (c)nicotine + water (d) ethanol + water
)
-olubilit$ -olubili t$ of following decrease with increase in temp (a)Ce2(-O") (b)CaCl2 /%2O (c)#b(0O) 2 (d)9 2Cr2O
&) .he unit of of
c) /x1'=2Cmm mm d) ll of the these se
*) Convert 1/' mm %g into 9pa KKKKKKKK a) 229pa b) 2129pa c) 2"129pa
d) 219pa
/') .he mass of one mole of electron electron is KKKKKKKKK a) '&mg b)'mg c) "& L 1' = 9g 9g
d) ll of b4 c
/1) .he order of the rate rate of di3usion of gases 0% 4 -O24 Cl2 and CO2 is KKKKKK a) 0% 5 -O2 5 Cl2 5 CO2 b) 0% 5 CO2 5 -O2 5 Cl2 c) CO2 5 0% 5 -O2 5 Cl2 d) -O2 5 0% 5 CO2 5 Cl2 /2) .he number of bonds in 02 molecule are are KKKKKKKKKK a) 1M 2N b) 1M 1N c) 2M 1N
d) M
/) Which of the following molecule has Bero dipole moment KKKKKKKK a) 0% b) %2O c) ChCl d) A! /") Which of the following has unpaired unpaired electrons in antibonding antibonding molecular orbitalKKKK a) 02=2 b) O2+2 c) A2 d) !2 /) d=orbitals have number of degenerate orbitals orbitals KKKKKKKKK a) / b) c) " d) //) //) -nCl -nCl" shows geometr$ KKKKKKK a) .rigonal b) ngular
c) #$ramidal
d) .etrahedral
/) Correct geometr$ for .rans 142 = dichloroethene is KKKKKKKKK a)
b)
c)
d)
/&) >nite of b in 7an
d) dm mo molle=1
c) ?eddish Arown
d) Arown
') .he rate of evaporation evaporation increases when KKKKKKKKKKKK a) 6ncrease in . b) 6ncrease in -urface rea c) Wea, forces Jc 1) 6n winter the viscosit$ of blood KKKKKKKKKK KKKKKKKKKK a)
2) One d$ne is e;ual to KKKKKKKKK a) 1'= 0 b) 1'= 0
c) Constant
c) 1'=/ 0
d) ll a4b
d)
d) 1'= 0
) ;ual masses of methane and ox$gen ox$gen are mixed in an empt$ container at 2 oC4 the fraction of total pressure exerted b$ O 2 isKKKKKKKK a) &E* b) 1E c) 1E* d) E1 ") .he percentage percentage of 0itrogen in >rea (0% 2)2CO is KKKKKKKKKKK a) "/ b) "" c) "' d) " ) .he molecules of which of the following gases have the greater average average molecular speed at ''9 a) rgon b) 0eon c) !lourine d) Chlorine /) 6n 0aCl4 each 0a+1 ion is surrounded b$ KKKKKKKKKK a) " Cl =1 io ions b) Cl=1 io ions c) / Cl=1 ions
d) 2 Cl=1 ions
) -alts which absorbs moisture from the atmosphere atmosphere are called KKKKKKKKK a) %$droscopic salt b) Celtic salt c) 9osher salt d) %$groscopic salt &) #robabilit$ of finding the electrons electrons in N bond is KKKKKKKKKKK a) @inimum at nodal plane b) @aximum at nodal plane c) @aximum in the region region above and below nodal nodal plane d) Aoth aJc aJc *) *) #% is an example of KKKKKKK a) A t$ t$pe
b) b t$pe
c) A22 t$ t$pe
d) A2 t$pe
&') t normal normal boiling point of substance4 the vapour pressure pressure of the substance KKKKKKKKKK
a) ;ual to /'cm of %g c) ;ual to /'torr
b)
&1) 6f the maximum area of orbitals is shared during overlapping4 overlapping4 it means KKKKKKK a) @aximum energ$ loss b) @inimum energ$ loss c) nerg$ sta$s constant d) @aximum gain of energ$ &2) 6f the temperature temperature and pressure of 2dm of CO2 are doubled4 then volume of CO 2 would become a) & dm b) / dm c) " dm d) 2 dm &) 6f 1'g of a gas at 1atm pressure pressure is cooled from 2 'C to ' 'C at constant volume4 it8s pressure would become KKKKKK a) 2atm b) 1atm c) P atm d) 2atm &") .he densit$ of methane at 2atm pressure pressure and at 2 'C is KKKKKK a) 2/ g dm= b) '2/ g dm= c) 1' 1 ' g dm = d) '1g dm= &) .he spreading spreading of fragrance of perfume perfume in air is due to KKKKKKKK a) 3usion b)
IMPORTANT SHORT QUESTIONS FROM ALL CHAPTERS Wh$ M2#x is not e;ual to N2#$4 N2#B according to molecular orbitals energ$ level although the$ all are degenerate orbitals pu3 of smo,e weighs '1 gram %ow man$ atoms are present (ssume smo,e is pure Carbon) Wh$ eEm value of cathode ra$s is same for all gases Hustif$ that the distance distance gap between di3erent di3erent orbitals increases increases from lower lower to higher orbitals photon of wave number 1'2' L 1'm=1 Iumps from from higher orbital to n F 1 !ind the number of orbit from where the electron falls !ind the percentage composition of 0itrogen 0it rogen in 0% 2CO0%2 Wh$ -i!" does not show nite positive charge 1/'22x1'=1* C) Where is the maximum probabilit$ of finding the electrons in M and N bond !ind the value of 6deal gas constant when units are cm torr mol=1 9 =1 Wh$ water vapors do not behave ideall$ at 29 Wh$ water boils at 12' 'C in pressure coo,er
sing Aohr8s e;uation calculate the distance travelled b$ an electron of a %$drogen atom when it Iumps from 1st to 2nd orbit Write three properties of canal ra$s se the concept of %$drol$sis to explain wh$ a;ueous solutions of some salts are acidic4 basic or neutral4 2HBr(g) Write rate e;uation (rate law) of the reaction and deduce overall order of reaction Calculate the mass percent of a solution containing 1' grams of sugar and 1'' grams of water >sing ?aoult8s law prove that the ?elative Rowering of vapour pressure is e;ual to the mole fraction of the non=volatile4 non= electrol$te solute What is lioniBation energ$ Wh$ is the 1st 6 V 2 nd 6 and so on Wh$ does the 6 increase along the period Wh$ do the boiling points of noble gases increase down the groupO !reshl$ cut surface of the metal m etal is shin$ shin $) Wh$O What is order of reactionO Qive an example of Bero order reactionO
S&'l#(at#o% xplain wh$ heat of sublimation of a substance is greater than heat of vaporiBation) -tate and explain %ess8s law using a general reaction) Aalance the following ?edox e;uation b$ using oxidation number method: NaCI02 + Cl 2 NaO + CI02
