Gold leaching in an aerated cyanide solution takes place according to the reaction: au+8cn22h20-4au(cn)2+4oh assume that the mass transfer of dissolved oxygen to the gold surface controls the rate. calculate the initial rate (g s) of dissolution of a spherical 100 μm (diameter) gold particle suspended in an aerated solution containing excess cyanide, atomic mass: o- 16, au- 197 concentration of dissolved oxygen in water 8 mg l mass transfer coefficient for a 60 μm gold particle 1 x 10-3 cm s-1

all eukaryotic cell have mitochondria : )

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2