a. mass of iron = 69.92 g
b. percent yield = 93%
<h3>Further eplanation
</h3>
Percent yield is the compare of the amount of product obtained from a reaction with the amount you calculated
General formula:
Percent yield = (Actual yield / theoretical yield )x 100%
An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients
a.
Reaction
Fe₂O₃+3CO⇒2Fe+3CO₂
MW Fe₂O₃ : 159.69 g/mol
mol Fe₂O₃

mol Fe₂O₃ : mol Fe = 1 : 2
mol Fe :

mass of Fe(Ar=55.845 g/mol) :

b.
actual yield = 65 g
theoretical yield = 69.92 g
percent yield :

Group 4A
The elements in group 4 show the most diverse set of properties.
Answer:
176984.38J
Explanation:
E = mC∆T
Where E is the energy in joules
M is the mass of water
C is the specific heat capacity of water =4.184J/g°C
It is known that it will take 4.184J of energy to change the temperature of water by one degree Celsius.
∆T = 98.6°c - 5.4°c
= 93.2°c
∆H = 454.3g × 4.18J/g°C × 93.2°c
= 176984.3768
176984.38J