--%>
Assignment Help - homework help

Problem on melting of ice

A) It has been suggested that the surface melting of ice plays a role in enabling speed skaters to achieve peak performance. Carry out the following calculation to test this hypothesis. Suppose that the width of the skate in contact with the ice has been reduced by sharpening to 0.25 mm. and that the length of the contact area is 15 cm.

i) If a skater of mass 85 kg is balanced on one skate, what pressure (in bar) is exerted at the interface of the skate and ice?

ii) If the temperature of the ice is -5.0°C, do you expect melting of the ice at the ice-skate interface to occur? Why?

B) At what temperature does water boil on the top of Mount Everest, the elevation h = 8848m? Use only the following information to obtain your estimate:

-Dependence of pressure with the altitude is given by

P = Patm exp [(-MWgh)/RT]

where, Patm is atmospheric pressure, g is the gravitational acceleration, MW is the molecular weight of air and T is average temperature (=273 K).

-Normal boiling point (B.P.) of water is 100°C.

-The latent heat of vaporization of the water is 2257 KJ/Kg.

   Related Questions in Chemistry

  • Q : Question based on lowest vapour pressure

    Give me answer of this question. Among the following substances the lowest vapour pressure is exerted by: (a) Water (b) Mercury (c) Kerosene (d) Rectified spirit

    		•
  • Q : What are Vander Waal's Radii? Vander

    Vander Waal's radii can be assigned to the atoms of molecules on the basis of the closeness of approach of these atoms in crystalline substances. Diffraction studies of crystals give information about hoe molecules can approach each other and can pack

    		•
  • Q : Explain structure basicity of amines.

    Basic character of amines is related to their structural arrangement. Basic strength of amines depends on the relative ease of formation of the corresponding cation by accepting a proton from the acid. Greater the stability of cation is, more is basic strength of amine.Alkyl a

    		•
  • Q : Define the term oxidizing agent Briefly

    Briefly define the term oxidizing agent?

    		•
  • Q : Which is polar HCl or HF Which one is

    Which one is polar HCl or HF?

    		•
  • Q : What are heterogenous catalysis? Give

    When the catalyst exists in a different phase than that of reactants, it is said to be heterogeneous catalyst, and the catalysis is called heterogeneous catalysis. For example, SO2 can be oxidized to SO3

    		•
  • Q : Determining concentration in ppm A 500

    A 500 gm tooth paste sample has 0.2g fluoride concentration. Determine the concentration of F in terms of ppm level: (a) 250 (b) 200 (c) 400 (d) 1000Answer: (c) F-ions in ppm = (0.2/500) x 106 = 400

    		•
  • Q : Modern periodic table and Mendeleevs

    Differentiate between the modern periodic table and Mendeleevs table?

    		•
  • Q : What is Spectroscopy? This is a very

    This is a very important aspect of Physical Chemistry in which knowledge of the size, shape, rigidity and electronic structure of molecules deduced from the experimental methods treated here goes hand in hand with the theoretical approaches of chemical reactions. Spec

    		•
  • Q : Mole fraction of hydrogen Give me

    Give me answer of this question. In a mixture of 1 gm H2 and 8 gm O2 , the mole fraction of hydrogen is: (a) 0.667 (b) 0.5 (c) 0.33 (d) None of these

    		•