A vapour-liquid mixture of water (1) and furfural C5H4O2 (2) is maintained at 1.013 bar and 109.5 oC. Under these conditions, it is found that x1 = 0.10 and y1 = 0.81. The temperature of the mixture is changed to 100.6 oC, and some (but not all) of the vapour condenses. The vapour phase may be assumed to behave as an ideal gas. The liquid-phase activity coefficients are independent of temperature but vary with concentration according to the van Laar equations. Determine: The activity coefficients for water and furfural at 1.013 bar and 109.5 oC and the van Laar constants Vapour pressure data T= 100.6degrees p^sat1= 1.0352 bar, p^sat2=0.1193bar
T=109.5degrees p^sat1=1.4088bar p^sat2=0.1690bar

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

hey there!

mass = 6.75 g

volume =   9 cm³

therefore:

d = mass / volume

d   = 6.75 / 9

d = 0.7 g/cm³

answer b