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
Very bad written question
C, then, D, A
1) Chemical equation
16Fe(s) + 3S8(s) ---> 8Fe2S3
2) Molar ratios:
16 mol Fe : 3 mole S8 : 8 mol Fe2S3
3) Convert masses in grams to number of moles
number of moles = mass in grams / molar mass
a) iron, Fe
mass = 3.0 g
atomic mass = 55.845 g/mol
=> number of moles of Fe = 3.0g / 55.845 g/mol = 0.0537 mol
b) Sulfur, S8
mass = 2.5 g
molar mass = 8*32.065 g/mol = 256.52 g/mol
=> number of moles of S8 = 2.5g / 256.52 g/mol = 0.009746 mol
4) Limiting reactant
Theoretical ratio actual ratio
16 mol Fe / 3 mol S8 0.0537 mol Fe / 0.009746 mol S8
5.33 5.50
So, there is a little bit more Fe than the theoretical needed to react all the S8, which means the S8 is the limiting reactant.
5) Calculate the number of moles of iron (III) produced with 2.5 g (0.009746 moles) of S8
3moles S8 / 8 moles Fe2S3 = 0.009746 moles S8 / x
=> x = 0.009746 * 8 / 3 moles Fe2S3 = 0.026 moles Fe2S3
6) Convert 0.026 moles Fe2S3 into grams
mass in grams = number of moles * molar mass
molar mass of Fe2S3 = 207.9 g/mol
mass = 0.026 mol * 207.9 g/mol = 5.40 g
7) Answer: option D)
Answer:
hot, less, rise, top, cold, closer, more, sink
Explanation:
I'm in high-school done this long time ago
Answer:
itd be B because the melting point is 29.76 no matter the size
Explanation:
