Calculations With  Information -  Question  #2     Answers

Given the following information:

Lithium occurs in trace amounts in most rocks with the average content of the earth's crust being estimated at 0.006%.  It is frequently a minor constituent of natural brines and spring waters.

Lithium is mined from open pits.  The primary source is spodumene (lithium aluminum silicate) LiAl(SiO3)2 or LiAlSi2O6.  Extensive deposits of spudomene are found in Quebec.

The commercial production of lithium in the world has been important only since 1930.  Lithium never occurs in the free state. Forty-two percent of the grease used in the United States contains lithium soap. The wing skins on an aircraft operating at Mach 2 are constructed from a lithium-aluminum alloy.

Find the following:

a)  Mass of one mole of  lithium aluminum silicate                                ____ g

b)  Percent of lithium in spudomene                                                        ____ %

c)  Percent aluminum in spudomene                                                       ____ %

d)  Percent silicon in spudomene                                                             ____ %

e)  Number of moles of LiAl(SiO3)2 in 137.25 g of the compound        ____ mol

f)  Number of grams of Li that could be obtained from 350.75 g of
    lithium aluminum silicate                                                                     ____ g

g)  Number of grams of Li that could be obtained from 18.25 kg of
     LiAl(SiO3)2                                                                                          ____ g