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.
To find out the number of water molecules produced simply use Avogadro’s constant, where 1 mol of any compound is equal to 6.02 x 10^23 molecules of the substance.
Multiply 0.815 to this value.
Answer:
B. Green solution density is 1.06 g/ml and blue solution density is 1.20 g/ml
Explanation:
Density is given as,
D = Mass / Volume
Red Solution,
D = 25 g / 25 mL
D = 1 g/mL
Green Solution,
D = 26.5 g / 25 mL
D = 1.06 g/mL
Yellow Solution,
D = 28.2 g / 25 mL
D = 1.128 g/mL
Blue Solution,
D = 30 g / 25 mL
D = 1.20 g/mL
B. Slower than the gas is the answer
2.a) warm air is lighter than cold air so thats why it's warmer upstairs than downstairs
3.d) Conduction<span> is the process by which heat energy is transmitted through contact with neighboring molecules</span>
4.d) the lamp radiates heat throughout the plants
