--%>
Assignment Help - homework help

Problem on physical and thermodynamic properties

The shells of marine organisms contain calcium carbonate CaCO3, largely in a crystalline form known as calcite. There is a second crystalline form of calcium carbonate known as aragonite. Physical and thermodynamic properties of calcite and aragonite at 298 K and 1.0 bar are given in the following table.

1344_calcite.jpg

i) Would you expect an isolated sample of calcite at 298 K and 1.0 bar to convert to aragonite via the reaction (or phase transition)

CaCO3calcite → CaCO3aragonite

given sufficient time? Explain.

ii) Determine the minimum pressure that must be exerted on calcite at 298 K to form aragonite. Assume that calcite and aragonite form pure solid phases that are incompressible and insoluble in each other.

iii) Can calcite be converted to aragonite at P = 1.0 bar if the temperature is increased? Explain.

   Related Questions in Chemistry

  • Q : Problem on moles of solution The number

    The number of moles of a solute in its solution is 20 and total no. of moles are 80. The mole fraction of solute wil be: (a) 2.5 (b) 0.25 (c) 1 (d) 0.75

    		•
  • 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 : Problem on reversible and irreversible

    The second law states that  dS ≥ (dQ/T), where dS = dQ/T for a reversible process and dS > dQ/T for an irreversible process.   a. Show that since dW12 = -dW21 (dWreverse = -dWforward) for a r

    		•
  • Q : Meaning of molality of a solution The

    The molality of a solution will be: (i) Number of moles of solute per 1000 ml of solvent (ii) Number of moles of solute per 1000 gm of solvent (iii) Number of moles of solute per 1000 ml of solution (iv) Number of gram equivalents of solute per 1000 m

    		•
  • Q : Explain group 15 elements. The various

    The various elements

    		•
  • 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 : Units of Measurement Unit of

      Unit of measurement- These are also some systems for units:      (1) 

    		•
  • Q : Means of molal solution Choose the

    Choose the right answer from following. A molal solution is one that contains one mole of a solute in: (a) 1000 gm of the solvent (b) One litre of the solvent (c) One litre of the solution (d) 22.4 litres of the solution

    		•
  • Q : Problem on vapour pressure Choose the

    Choose the right answer from following. If P and P are the vapour pressure of a solvent and its solution respectively N1 and N2 and are the mole fractions of the solvent and solute respectively, then correct relation is: (a) P= PoN1 (b) P= Po N2 (c)P0= N2 (d)

    		•
  • Q : Quantum Mechanical Operators The

    The quantum mechanical methods, illustrated previously by the Schrödinger equation, are extended by the use of operators. Or, w

    		•