The correct answer in here is: Limited the burning of soft coal. Some reasons for that are that when Britain was the workshop of the world its coal consumption increased from around 10 million tons per annum in 1800 to almost 200 million tons in 1950 and also that <span>Coal smoke was linked to very high death rates from respiratory diseases such as bronchitis, killing between 800,000 and 1.4 million people in the period 1840-1900.</span>
Answer:
The correct answer is:
A solution feels warm after a cool solid is added to it (C)
Explanation:
Chemical changes among other results in a change of the temperature of the reactants, producing a product of higher temperature (exothermic reaction) or a product of lower temperature (endothermic reaction). In this case, the temperature of the product was higher than the reactants suggesting an exothermic reaction.
The other options however, suggests physical changes rather than a chemical changes;
A. the change of color of the water suggest mixing or water and color molecules.
B. solid changing into liquid is change of state, which is more of a physical change than chemical
D. Filtration is a physical process, hence the change is a physical change.
Answer:
Explanation:
There is a formula for this:
M = DRT/P where M = molar mass. This just derived from PV = nRT where you say n = grams/molar mass. However, just with this formula, we can get D which is density at STP (1 atm and 273K). We find that D = 6.52g/L.
Answer:
1.39
Explanation:
[Hg2Cl2]= 1M
[H^+] = ????
E°cell= 0.35V
E= 0.268 V
Therefore E for the reaction must -0.082 V
n= 2 moles of electrons
From Nernst Equation:
E= E°cell- 0.0592/n log [Red]/[Ox]
0.0268= 0.35- 0.0592/2 log 1/[Ox]^2
-0.082= -0.0296 log 1/[Ox]^2
log 1/[Ox]^2= 0.082/0.0296
log 1/[Ox]^2= 2.77
1/[Ox]^2=Antilog (2.77)
[Ox]^2=1.698×10^-3
[Ox] = 0.0412 M
But pH= -log [H^+]= -log(0.0412)= 1.385
Answer:
The boiling point is 308.27 K (35.27°C)
Explanation:
The chemical reaction for the boiling of titanium tetrachloride is shown below:
Ti
⇒ Ti
ΔH°
(Ti
) = -804.2 kJ/mol
ΔH°
(Ti
) = -763.2 kJ/mol
Therefore,
ΔH°
= ΔH°
(Ti
) - ΔH°
(Ti
) = -763.2 - (-804.2) = 41 kJ/mol = 41000 J/mol
Similarly,
s°(Ti
) = 221.9 J/(mol*K)
s°(Ti
) = 354.9 J/(mol*K)
Therefore,
s° = s° (Ti
) - s°(Ti
) = 354.9 - 221.9 = 133 J/(mol*K)
Thus, T = ΔH°
/s° = [41000 J/mol]/[133 J/(mol*K)] = 308. 27 K or 35.27°C
Therefore, the boiling point of titanium tetrachloride is 308.27 K or 35.27°C.