8.769 of impure sample containing H2C2O4(s) was dissolved completely in 250 cm3 of distilled
water to form a solution . 25.0cm3 of this
Solution was pipetted out in a conical flask
and titrated with 0.0650 moldm^-3 acidified
K2Cr2O7(aq). 31.80 cm ^3 of K2Cr2O7(aq) was
used . Calculate the percentage purity of
the sample.

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Following are the  advantages of the parametric equations: 1) they can be used to graph curves that are not functions, like the unit circle.2) the parameter can be used to represent the quantity that is  useful to  provide us with better information about the graph.3)  it is useful to convert between rectangular equations and parametric equations.with specific reference to chemistry,  parametric equations are employ for solving hydrogen and hydrogen-like ions, quantum mechanically. herein, cartesian coordinates are converted in spherical polar coordinates. the solution obtained, when plotted on spherical polar graph paper, provides visualization of atomic orbital such as s,p,d and f. 

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