os x physics

Astbury, by his X-ray diffraction studies, suggested three dimensional configuration for DNA molecule due to its high density. The purines and pyrimidines seemed to be flat rings arranged at right angles to the sugar-phosphate backbones and stacked one above another. The successive ..

a) joule = coulomb x volt b) volt = coulomb x joule c) coulomb = volt x joule d) volt = joule - coulomb. [a] 16. The S.I. unit of resis tance is called a) ohm b) joule c) ampere d) coulomb. [a] 17.. If 20 J of work is done in moving a charge of..

Natural sources of radiations to which humans are exposed such as ultraviolet rays from the sun, cosmic rays from space and emissions from naturally occuring radioactive elements cause skin cancer. Medical, industrial and military activities have created additional sources of high energy rad..

Hydrogen is a colourless, odourless and tasteless gas. Its density is 1 g/ml. Its boiling and melting pbints are 20.4 K and 13.8 K respectively. Its enthalpy of fusion is 0.117. KJ/mole, whereas its enthalpy of vaporisation is 0.904 KJ/mole. Hydrogen molecule has H - H bond and its bond leng..

Time: 70 min. Max. Marks: 60 1. Which of the following does not depend on temperature? (1) half life period (2) rate constant (3) number of activated molecules (4) order 2. On January 1st of last year, 16 g of a radioactive isotope was packed in a closed container. The container was open..

. The container was opened on June 1st, only 0.5 gram of the isotope remind. The half life of the isotope is (1)30 days (2) 25 days (3) 40 days (4) 10 days 3. Identify the reaction which does not belong to the group with respect to order given (1) dissociation of hydrogen halide on gold surface (2)..

Physical properties The first three members are gases. Alkenes from c4 to C ]5 are liquids. Higher members are solids. Except ethylene, which has a sweetish odour, all the other members are odourless. Chemical properties Alkenes are more reactive than alka..

(4) lowering of vapour pressure ^ 39. What is the relative lowering of vapour pressure when 12 g of urea is dissolved in 90 g of water (1) 0.025 pascal (2) 0.062 pascal (3) 0.038 pascal ~ (4) 0.4 pascal .40. Two chambers A (solution of a non-volatile solute) and B (solvent) are sep..

It is most important to know the accuracy of a measured physical quantity with the apparatus available in the laboratory. Hence the relative error percentage in the measurements of a physical quantity is to be taken into account. From this, it is not only possible to know th..

Physical Properties of Organic Halides (1) Boiling points of monohaloalkanes are higher than corresponding alkanes containing same number of carbon atoms, e.g. boiling point of chloromethane (-24 C) is higher than that of methane (-164 C) (2) For monohaloalkane compounds..