lithium borohydride crystallises in orthorhombic system with 4 molecules per unit cell.the unit cell dimensions are a=6.8A,b=4.4A,c=7.2A.if molar mass is 21.76,calculate density of cry

Dear shefali

volume of the unit cell = abc =6.8*4.4*7.2 =215.424 A³  = 2.154 *10^-22 cc

each unit cell has 4 molecules  so mass of each unit cee  = 4*21.76/(6.023 *10²³)

                                                                                =1.445 * 10^-22  gm

so density =1.445 * 10^-22  gm/2.154 *10^-22 cc 

                    =.671 gm/cc

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