Recently Active Chemistry Questions

1.... why gamma rays do nt effect photographic screen despite hving high frequency ?????/ is it due to their non material nature????..........wat are constituent particles of gamma rays???? ...

what is velocity constant 'k' of a reaction????? ...

As we known , the number of unpaired valence electrons is the valency therebye, Boron (2s2 2p1) should have monovalency , but it is invariably trivalent , never monovalent why ? ...

Pb(IO3)2 a sparingly soluble salt in water has a Ksp= 2.6*10-13 . To 35 mL of a 0.15 M Pb(NO3)2 solution, 15 mL of a 0.8 M KIO3 is added and a ppt. is obtained. Find the concentrations of Pb2+ and IO32- left in the solution. ...

Consider a large hollow sphere of radius 'R' in which small solid sphere of radius 'r' has to be placed in closest pascking. ( assume r=R/10) 1) Maximum no. of small spheres that can be filled into the large hollow sphere are ...

In mineral A2B, atoms B form CCP structure while A atoms occupy the voids within this structure. What are the coordination numbers of atoms A and B ? Name the voids in which atoms A are present and what fraction of these void ...

Streptimidone is an antibiotic and has the structure shown. How many stereoisomers of streptimidone are possible? How many enantiomers? Using the E,Z and R,S descriptors, specify all the essential elements of stereochemistry ...

Identify Inorganic salt (A) which is hydrated and light green in colour and gives following reactions : (i) (A) decolorises acidified MnO4-and turns acidified Cr2O72- green. (ii) (A) in aq. solution gives light green turbidit ...

He can be excited to 1s1 2p1 configuration by light of 58.44 nm . The lowest excited singlet state , with the configuration 1s 1 2s 1 , lies 4857 cm-1 below the 1s1 2p1 state . What would be the average He - H bond energy hav ...

when we mix solute in solvent to prepare a non ideal solution showing +ve deviation the solution becomes (1)hot (2)cold (3)may become cold or may be hot (4)none of these answer with explanation ...

Which of the following statement(s) is/are true regarding Langmuir's absorption isotherm ? A. It explains only mono layer absorption. B. Molecules absorbed at one site do not interact with surrounding adsorbate molecules. C. ...

What is the effective nuclear charge at the periphery of nitrogen atom when an extra electron is added in the formation of an anion.Compare this value when the atom is ionised. ...

(IE)1 and (IE)2 of Mg(g) are 740 and 1450 kJ mol-1. Calculate percentage of Mg+(g) and Mg2+(g) if 1 g of Mg(g) absorbs 50.0 kJ of energy. ...

which is /are correct about emulsions? 1>demulsification can take place by chemical method only 2>small amount of water can not be mixed in water in oil emulsion 3>sodium oleate is used to prepare oil in water emulsi ...

This thread will focus on some very basic things of organic chemistry. They mainly will help to solve problems that are based on passage type questions. Feel free to contribute. Please do not post everything in a single post. ...

Q1 peptization is a) evaporation of dispersed med b)precipiation of dispered phase c)disintegration of dipersed phase d)combined effect of dispersion medium on dispersed phase Q2 Colloidal particles of water are coagulated ef ...

Oxalic acid decomposes in presence of UO22+ & loses its property. This is used in estimating the amount of decomposed acid & quantum efficiency of the process Here efficiency = 50 % . 1L of 0.005 M oxalic acid solution was ir ...

Among the following compounds,which will react with acetone to give a product containing C *Image* N bond ?? A. C6H5NH2 B. (CH3)3N C. C6H5NHC6H5 D. C6H5NHNH2 ...

Use data from Figure to determine whether a solution containing 48 g of KNO3 per 100 g of water at 40 °C is saturated, unsaturated, or supersaturated *Image* ...

In the reaction p-chlorotoulene with KNH2 in liq NH3 major product is A. o-toulidine B. m-toulidine C. p-toulidine D. p-chloroaniline ...

*Image* How will the divalent nitrogen affect the stability of the species? ...

Explain the order of basicity of the following compounds in (i) Gaseous phase and (ii) inaqueous soln. : (CH3)3N, (CH3)2NH, CH3NH2, NH3 Give Proper Explanation. ...

ARRANGE THE FOLLOWING IN DECREASING ORDER OF BASICITY. eXPLAIN THE REASON AS WELL. *Image* ...

n0/2 atoms of X(g) are converted in to X+ (g) by energy ∆H,KJ .n0/2 atom atoms of X(g) are converted in to X+(g) and n0/2 atoms of X(g) converted in to X-(g) by energy ∆H2. calculate the ionization energy and electron aff ...

Why do Mno4- and Cr2O72- show color? ...

*Image* What is the Product in above Problem? ...

Why does monobromination of acetanilide proceed faster than benzene? ...

Why does decarbonylation take place in acylation? ...

Methylenomycin A is a potent antibiotic isolated from Streptomyces violaceoruber. Answer the following questions about methylenomycin A. *Image* i) Identify the stereogenic (chiral) centers in Methylenomycin A. Determine whet ...

1,2 dichloro propane+(alc.)KOH------->?? this question was posted quite earlier,but i want to revive the disscussion hints:think of E1,E2 and Sn2 ...