Answer:
the entropy change for the surroundings when 1.68 moles of Fe2O3(s) react at standard conditions = 49.73 J/K.
Explanation:
3Fe2O3(s) + H2(g)-----------2Fe3O4(s) + H2O(g)
∆S°rxn = n x sum of ∆S° products - n x sum of ∆S° reactants
∆S°rxn = [2x∆S°Fe3O4(s) + ∆S°H2O(g)] - [3x∆S°Fe2O3(s) + ∆S°H2(g)]
∆S°rxn = [(2x146.44)+(188.72)] - [(3x87.40)+(130.59)] J/K
∆S°rxn = (481.6 - 392.79) J/K =88.81J/K.
For 3 moles of Fe2O3 react, ∆S° =88.81 J/K,
then for 1.68 moles Fe2O3 react, ∆S° = (1.68 mol x 88.81 J/K)/(3 mol) = 49.73 J/K the entropy change for the surroundings when 1.68 moles of Fe2O3(s) react at standard conditions.
Answer:
C3H6O3
Explanation:
To find the emperical of the compound,you divide the percentage composition of each element by it's molar mass(C=12, H=1, O=16).
For C,40/12=3.33. For H,6.71/1=6.71
For O,53.19/16=3.33.
Then divide everything by the smallest value which is 3.33
For C,3.33/3.33=1. For H,6.71/3.33=~2.
For O,3.33/3.33=1.
Emperical formula=CH2O
Molecular formula=(CH2O)n=90
(12+2*1+16)n=90
30n=90, n=3
molecular formula=(CH2O)3
molecular formula of lactic acid=C3H6O3.
Answer:
Iron: Fe
Co: Cobalt
Na: Sodium
Tin: Sn
P: Phosphorus
F: Flourine
Fe: Iron
Magnesium: Mg
Uranium: U
Ca: Calcium
Carbon: C
Lead: Pb
Ag: Silver
Zn: Zinc
Ni: Nickle
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There is honestly no right answer for this but here is what I would put:
Atomic mass increases as you go from left to right. If you look at the periodic table, it would be between Sn and Sb. It would bet here because Sn is 118 and Sb is 121. Basing it off of Antimony and putting it in group 15, the properties are that it is metallic and is a poor conductor of heat. I would call it Stin, which would be shortened to St.
if we did not use an excess of the BaCl2 solution it would decrease the mass percentage of sulfate in the unknown sample.
The net precipitation equation would be.
Ba2+(aq) + SO42-(aq) → BaSO4(s)
If BaCl2 (Ba2+) is not taken in excess then the precipitation would not be completed as some of the sulfate ions would still be remaining in the solution. This would decrease the mass percentage of sulfate in the unknown sample.
If some tiny pieces of filter paper still remained mixed with the precipitate(BaSO4) then the mass of sulfate would increase and it gives a high mass percentage of the sulfate.
mass percentage of sulfate = (mass of sulfate/mass of sample)*100
Learn more about precipitation here brainly.com/question/14675507
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Answer:
Light waves carry energy parallel to the motion of the wave, while sound waves carry energy perpendicu
Explanation:
