1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ExtremeBDS [4]
3 years ago
14

ANSWER ASAP AND I WILL GIVE BRAINLYEST!!!!

Chemistry
1 answer:
Vlada [557]3 years ago
6 0

Answer:

20m

Explanation:

mark brainliest

You might be interested in
At what temperature is the following reaction feasible: HCl(g) + NH3(g) -> NH4Cl(s)?
Nutka1998 [239]
Energy is distributed not just in translational KE, but also in rotation, vibration and also distributed in electronic energy levels (if input great enough, bond breaks).

All four forms of energy are quantised and the quanta ‘gap’ differences increases from trans. KE ==> electronic.

Entropy (S) and energy distribution: The energy is distributed amongst the energy levels in the particles to maximise their entropy.

Entropy is a measure of both the way the particles are arranged AND the ways the quanta of energy can be arranged.

We can apply ΔSθsys/surr/tot ideas to chemical changes to test feasibility of a reaction:

ΔSθtot = ΔSθsys +  ΔSθsurr

ΔSθtot must be >=0 for a chemical change to be feasible.

For example: CaCO3(s) ==> CaO(s) + CO2(g) 

ΔSθsys = ΣSθproducts – ΣSθreactants 

ΔSθsys = SθCaO(s) + SθCO2(g) – SθCaCO3(s) 

ΔSθsurr is –ΔHθ/T(K) and ΔH is very endothermic (very +ve),

Now ΔSθsys is approximately constant with temperature and at room temperature the ΔSθsurr term is too negative for ΔSθtot to be plus overall.

But, as the temperature is raised, the ΔSθsurr term becomes less negative and eventually at about 800oCΔSθtot becomes plus overall (and ΔGθ becomes negative), so the decomposition is now chemically, and 'commercially' feasible in a lime kiln.

CaCO3(s) ==> CaO(s) + CO2(g)  ΔHθ = +179 kJ mol–1  (very endothermic)

This important industrial reaction for converting limestone (calcium carbonate) to lime (calcium oxide) has to be performed at high temperatures in a specially designed limekiln – which these days, basically consists of a huge rotating angled ceramic lined steel tube in which a mixture of limestone plus coal/coke/oil/gas? is fed in at one end and lime collected at the lower end. The mixture is ignited and excess air blasted through to burn the coal/coke and maintain a high operating temperature.
ΔSθsys = ΣSθproducts – ΣSθreactants
ΔSθsys = SθCaO(s) + SθCO2(g) – SθCaCO3(s) = (40.0) + (214.0) – (92.9) = +161.0 J mol–1 K–1
ΔSθsurr is –ΔHθ/T = –(179000/T)
ΔSθtot = ΔSθsys +  ΔSθsurr
ΔSθtot = (+161) + (–179000/T) = 161 – 179000/T
If we then substitute various values of T (in Kelvin) you can calculate when the reaction becomes feasible.
For T = 298K (room temperature)

ΔSθtot = 161 – 179000/298 = –439.7 J mol–1 K–1, no good, negative entropy change

For T = 500K (fairly high temperature for an industrial process)

ΔSθtot = 161 – 179000/500 = –197.0, still no good

For T = 1200K (limekiln temperature)

ΔSθtot = 161 – 179000/1200 = +11.8 J mol–1 K–1, definitely feasible, overall positive entropy change

Now assuming ΔSθsys is approximately constant with temperature change and at room temperature the ΔSθsurr term is too negative for ΔSθtot to be plus overall. But, as the temperature is raised, the ΔSθsurr term becomes less negative and eventually at about 800–900oC ΔSθtot becomes plus overall, so the decomposition is now chemically, and 'commercially' feasible in a lime kiln.
You can approach the problem in another more efficient way by solving the total entropy expression for T at the point when the total entropy change is zero. At this point calcium carbonate, calcium oxide and carbon dioxide are at equilibrium.
ΔSθtot–equilib = 0 = 161 – 179000/T, 179000/T = 161, T = 179000/161 = 1112 K

This means that 1112 K is the minimum temperature to get an economic yield. Well at first sight anyway. In fact because the carbon dioxide is swept away in the flue gases so an equilibrium is never truly attained so limestone continues to decompose even at lower temperatures.

8 0
3 years ago
Read 2 more answers
This is the process where fossil fuels, forests, or other carbon-containing substances are burned, adding more carbon dioxide to
sattari [20]
The process where fossil fuels, forests, or other carbon-containing substances are burned, addin more carbon dioxide to the air is the combustion.

Some examples of combustion are:

Fossil fuel:

Carbon + O2

C + O2 -> CO2

Forests (wood)

Wood = cellulose = [C6H10O5]n

[C6H10O5]n + 6nO2 = 6n CO2 + 5n H2O

So, in general the combustion of organic matter produces CO2 and water.


4 0
3 years ago
What causes the appearance of lines in an emission spectrum?
Nikitich [7]

Answer:

key concepts and summary. When electrons move from a higher energy level to a lower one, photons are emitted, and an emission line can be seen in the spectrum. Absorption lines are seen when electrons absorb photons and move to higher energy levels

Explanation:

thank me later

pls be brainlest

3 0
3 years ago
The benedict's test indicates a positive result when the solution turns.
aleksandrvk [35]
it turns yellow to orange
7 0
2 years ago
The following balanced equation shows the formation of sulfur dioxide.
AlexFokin [52]

actually the answer is C. 15.0 on ed

6 0
3 years ago
Read 2 more answers
Other questions:
  • In this task, you’ll observe a chemical reaction between baking soda and vinegar in water. write a hypothesis to predict the rel
    10·1 answer
  • X2o3 express you answer as a whole number
    5·1 answer
  • Carbon burns in the presence of oxygen to give carbon dioxide. Which chemical equation describes this reaction?
    15·1 answer
  • How does friction affect energy transformation
    13·2 answers
  • When 2.50g of hydrochloric acid reacts with 1.50g of potassium hydroxide to yiel
    12·1 answer
  • 2 NABr + Ca(OH)2 = CaBr2 + 2 NaOH How many moles of CaB 2 are produced, if 14.72 moles of NaBr and excess Ca(OH) 2 react?
    11·1 answer
  • Story that ends with I suddenly wake up and realize that it was a dream​
    12·1 answer
  • How would you compare a health care system in Ancient Egypt and a interdisciplinary health care team?
    7·1 answer
  • Solve the problem using dimensional analysis. Every number must have a unit. Work must be shown. Conversion factors are in the t
    10·1 answer
  • An aqueous solution contains the following ions: cl−, ag , pb2 , no−3, and so2−4. More than one precipitate will form. Identify
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!