Frequent Physical Chemistry Questions

Q1 what are the reactions involved when phosphoric acid h3po4 is titrated using naoh standard solution? Q2 when h3po4 is titrated using naoh solution, phenopthalien end point and methyl orange end points are observed clearly ...

*Image* please explain the concept clearly Q3.for a reaction ,rate expressions is given as----- RX+OH-=ROH +X- rate=4.7*10-5[RX][OH]+0.24*10-5[RX] wHAT PERCENT OF RX REACT BY SN2 ?WHEN [OH]=0.001M. ...

1) 4.9g of KClO3, on heating shows a wt loss of 0.384g. What per% of the original KClO3 has decomposed? 2) 1.84g of of a mixture of CaCO3 and MgcO3 was heated to a constant weight. The constant weight of the residue was found ...

Q1 Because of insufficient ignition, a supposed CaO precipitate from a 1 g sample of limestone weighed 0.4125 g and contained 5.3% of its own weight of CaCO3(ie there is CaCO3 left unignited whose amount is 5.3% of 0.4132) . ...

q.) d activity of a radioactivity isotope falls to 12.5% in 90 days. find decay constant. this ques. is solved in p bahadur.... it has used d eq. - K= 2.303/90 log 100/12.5 but d eq. shud be K= 2.303/90 log 100/87.5 na? since ...

A compound contains atoms of three elements:A, B and C.If the oxidation number of A is +2,B is +5 and C is -2,the possible formula of the compound is: a)A3(BC4)2 b)A3(B4C)2 c)ABC2 d)A2(BC3)2 ...

Mixture X=0.02 moles of [Co(NH3)5SO4]Br and 0.02 moles of [Co(NH3)5Br]SO4 was prepared in 2 L of solution: 1 L of mixture X+excess of AgNO3→Y 1 L of mixture X+excess of BaCl2→Z Number of moles of Y and Z are: a)0.01,0.01 ...

From 200 mg of carbon-dioxide,1021 molecules are removed.The amount of carbon-dioxide left is: a)120 mg b)150 mg c)126.9 mg d)100mg. ...

A compound contains 28% N and 72% of a metal by weight.3 atoms of metal combine with 2 atoms of N.Find the atomic weight of metal: a)38 b)30 c)24 d)18 ...

According to avogadro hypothesis: 1 mole of any gas at NTP/STP occupies a volume equal to =22.4L but according to gas theory a gas takes up the volume of any container in which it is kept ....then what is the use of avogadro' ...

1) If 5 litres of H2O2 produce 50 lites of O2 at NTP, H2O2 is a)50V b)10V c)5V d)250V I am not able to understand this question. What is it asking? 2)Assuming that petrol is octane & has density 0.8 g/ml, 1.425 litres of petr ...

1) What is detonating gas? 2)When the mixture of MgCO3 & CaCO3 was heated for a long time, the weight decreased by 50%. Calculate the percentage composition of the mixture. 3)Calculate the weight of V2O5 produced from 2g of V ...

WHAT mass of 60% HCl (by mass) is required to completely react with 0.2 mol of zinc.The reaction is : Zn +2HCl -> ZnCl2+H2 ...

2.76 gm of silver carbonate on heating strongly gives residue weighing? (Gram atomic mass of silver is 108 gm) ...

15.00 gm of a compound Na2SO4.xH2O contains 2.36*1023 H2O molecules.Find out the value of 'x' ...

what is the difference between atomic weight and gram atomic weight of any element??? ...

plz balance the following equations: 1)KMnO4 + FeSO4 + H2SO4->K2SO4 +MnSO4 + +Fe2(So4)3 + H2O [ by oxidation no. method ] 2) Cr2O7 + NO2- -> Cr3+ + NO3- [by half reaction method] ...

For the reaction, A⟺B,Kc=([B])/([A]) Kc<1 ⇒([B])/([A])<1⇒[B]<[A].If the concentration of reactants is more then the reaction must proceed in forward direction. But my book is writing that the reverse reaction i ...

Two jars A and B of equal capacity contain 10g of oxygen and 10g ozone respectively.Is the number of molecules equal in both jars?Which jar has greater number of atoms?Write the equation governing both parts or find the anoma ...

1) Calculate the molarity and molality of 20% aqueous of ethanol soln by volume (density of the soln=0.960g per cm3) 2) Calculate the volume of 80% H2SO4 (density=1.80g/cc) required to prepare 1L of 20% H2SO4 (density=1.25g/c ...

Q1- Can someone please tell me the exact and well described reason for depression of freezing point on addition of non volatile solute to a solvent? Q2- How does the vapour pressure of a pure solution change when we increase ...

http://targetiit4pcm.lefora.com/2010/06/16/articles-acids-and-bases-1/0/ hope you like it ...

1.An electrochemical cell is constructed by immersing a piece of copper wire in 50ml of 0.1M CuSO4 soln and " " ' ' zinc wire in " " " ZnSO4 soln. If 50 ml of 1.5 M NH3 is added to CuSO4 soln then Emf of cell is= Ans 0.715V g ...

0.4 gram hydrogen combines with 3.2 gram oxygen to produce water. H2S is produced by combination of 0.25 g hydrogen and 4.0 gram sulphur. 1 gram of sulphur combines with 1 gram of oxygen. Show that the results are in accordan ...

i have a basic doubt. Isnt order of a chemical reaction determined only experimentally ? i mean can we find order just by looking the balanced chemical eqn ? i think it can only be found out from the eqn for elementary reacti ...

*Image* I am really weak in chemistry ,so don't get upset abt the level of ques. ...

1.what are amphiprotic substances ? 2. which of the following is not an amphiprotic substances: a.h2o b.hco3-ve c.hso4-ve d.hpo4di-ve ...

what is fractional abundance in terms of isotopes while calculating atomic wt.? ...

What do you mean by"parts by weight of something" in general? Please also explain it in context with law of multiple proportions ...

1.If a solute undergoes dimerization & trimerization the minimum values of Van.t Hoff factor are.... 2.A complex is written as M(en)y.xBr.Its 0.05 molar soln shows 2.46 atm osmotic presure at 300 K.Assuming 100% ionistion and ...