Answer:
The percent yield of the reaction is 82%
Explanation:
First step: make the chemist equation.
2 Al (s) + Fe2O3 (s) → 2 Fe (s) + Al2O3 (s)
As the statement says that aluminun is in excess, the limiting reactant is the Fe2O3
Second step: Find out the moles in the reactant.
Molar weight Fe2O3: 159.7 g/m
Mass / Molar weight = moles
50 g /159.7 g/m = 0.313 moles
Third step: Analyse the reaction. 1 mol of Fe2O3 makes 2 moles of Fe.
1 mol Fe2O3 ____ 2Fe
0.313 mol Fe2O3 ____ 0.626 moles
Molar weight Fe = 55.85 g/m
Moles . molar weight = mass
55.85g/m . 0.626m = 34.9 grams
This will be the 100% yield of the reaction but we only made 28.65 g
34.9 g ____ 100%
28.65 g ____ 82.09 %
<span>In a solution of water and ethanol, hydrogen bonding is the strongest intermolecular force between molecules. Hydrogen bonding occurs when the partially negative oxygen end of one of the molecules is attracted to the partially positive hydrogenend of another molecule.</span>
Unfortunately, your question is incomplete So, according to the attached picture of the complete question we will explain the answer:
according to the reaction equation:
C(s) + 2H2(g) ↔ CH4(g) ΔH° = -74.6KJ
So the true answer will be
D i and ii
- as by adding more C and it is a reactant so the reaction will go rightward to the product to decrease the C to achieve the equilibrium again, the movement of the reaction towards the products will make the CH4 increase
- and by decreasing the Heat and the heat here is as a product as the reaction is exothermic so by decreasing the heat the reaction will go toward the products to increase the heat and achieve the equilibrium again, and that also makes the CH4 increase as it is a product.
So the true answer is
D i and ii as the attached photo
Answer:
Which statement are you looking for?
Answer and Explanation:
Calorie is the unit of heat energy . There are 2 units with the same name 'calorie' which is widely used.
'The amount of heat energy required to increase the temperature of 1 gram of water by mass by
or 1 K is known as small calorie or gram calorie'.
Another one is large calorie which can be defined as :
'The amount of heat energy required to make arise in temperature of water 1 kg by mass by
or 1 K is known as large calorie or kilcalorie and is represented as Cal or kcal'.
After the adoption of SI system, thee units of the metric system cal, C or kilocal are considered deprecated or obsolete with the SI unit for heat energy as 'joule or J'
1 cal = 4.184 J
1C or 1 kilocal = 4184 J
Calorimeter constant:
Calorimeter constant, represented as '
' is used to quantify the heat capacity or the amount of heat of a calorimeter.
It can be calculated by ther given formula:

where,
= corresponding temperature change
= enthalpy change
Its unit is J/K or J/1^{\circ}C[/tex] which can be convertyed to cal/1^{\circ}C[/tex] by dividing the calorimeter constant by 4.184 or 4184 accordingly.