An ideal gas, initially at 30°c and 100 kpa, undergoes the following cyclic processes in a closed system: (a) in mechanically reversible processes, it is first compressed adiabatically to 500 kpa, then cooled at a constant pressure of 500 kpa to 30°c, and finally expanded isothermally to its original state. (b) the cycle traverses exactly the same changes of state, but each step is irreversible with an efficiency of 80% compared with the corresponding mechanically revers- ible process. note: the initial step can no longer be adiabatic. calculate q, w, δu, and δh for each step of the process and for the cycle. take cp = (7/2)r and cv = (5/2)r.

the answer to this question is 3.

the answer is 1260

you spend 7 hours in school for 1 school day with 5 school days in 1 school week with 36 school weeks in a school year.

7*5*36= 1260 it's all about multiplying

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