In NiCD battery, a fully charged cell is composed of nickelic hydroxide. Nickel is an element that multiple oxidation states. Assume the proportions of the states.
Nickel Charge Proportions Found
0 0.17
+2 0.35
+3 0.33
+4 0.15
a. Determine the cumulative distribution function of nickel charge.
b. Determine the mean and variance of the nickel charge.

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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