Complete question:
Coal gasification consists of the chemical transformation of solid coal into gas. The heating values of coal differ, but the higher the heating value, the higher the value of the gas produced (which is essentially methane, carbon monoxide, hydrogen, etc.). The following coal has a reported heating value of 29,770 KJ/Kg as received. Assuming that this is the gross heating value, calculate the net heating value.. Component__________Percent C___________________71
H2__________________5.6
N2__________________1.6
S____________________2.7
Ash__________________6.1
O2___________________13
Answer:
LHV = 28478.8 KJ/kg
Explanation:
The gross heating value is also the higher heating value (HHV), while the net heating value is the lower heating value (LHV).
This involves the conversion from higher heating value (HHV) to lower heating value(LHV).
Let's use the formula:
LHV = HHV - 0.212H - 0.0245M - 0.008A
We are given
HHV = 29,770 KJ/kg = 29.770MJ/kg
H = hydrogen% =5.6%
A = oxygen% = 13%
M = 0
Substituting the figures in the formula, we have:
LHV = 29.770 - 0.212*5.6 - 0.0245*0 - 0.008*13
= 29.770 - 1.1872 - 0 - 0.104
= 28.4788 MJ/kg
= 28478.8 KJ/kg
LHV = 28478.8 KJ/kg
The net heating value, LHV = 28478.8 KJ/kg
Solutions for your questions are the following:
1. remaining amount is equal to:960 g : 100% = 30 g : xx = 30 g * 100% / 960 g
= 3.125%
= 0.03125
Now, we use this formula to calculate the number of half-lives:(1/2)ⁿ = x,
so,(1/2)ⁿ = 0.03125
to calculate n, use this equation:
n*log(1/2) = log(0.03125) n = log(0.03125)/log(1/2)
= log(0.03125)/log(0.5)
= -1.505/-0.301
n=5
Ifn = 5T = 15 min
Then
L = T/nL = 15 min/5
= 3 minutes
2. You should pick filtration. It is use to separate heterogeneous mixtures just like in the problem stated.
Answer:
The chemist can either:
a. Use a small fractionation apparatus.
b. Add a compound with a much higher boiling point.
Explanation:
Using a smaller fractionation apparatus or Vigreux column will help to minimize loss of the distillate.
If a compound with a higher boiling point is added, the vapors of this liquid will displace the vapors of this small amount of compound with a lower boiling point. This compound with a higher boiling point is known as a Chaser.
hope it helps please brainliest
Lots of substances. Rocks, metals, minerals, you name it.
