When you are dealing with mole calculations, whatever you do to one side of the equation you must also do to the other. .5Fe is 1/8th of 4Fe, so in order to determine what it will yield you must divide the given amount of Fe2O3 and divide THAT by 1/8th, leaving you with .25 mol of Fe2O3.
Answer:
When breaking a chemical bond, energy is absorbed by the chemical bond.
Explanation:
Chemical bonds are the forces of attraction that joins two chemical species. There are two types of chemical bonds: Strong Primary and Weak Secondary bonds.
When a chemical bond is formed between two species, it is accompanied by the release of energy. Therefore, <em>bond formation is an exothermic process</em>.
<u>However, energy is always required to break a chemical bond. As energy is needed to overcome the attractive forces present between the two species.</u> Therefore, <em>bond dissociation is an endothermic process.</em>
<u><em>Therefore, during bond dissociation, energy is absorbed by the chemical bond.</em></u>
An air conditioner uses chemicals that allow for the cooling of warm air, which makes it condense. Using that process over and over again allows the air conditioner to take the warm air outside, and the cold air inside. That's especially useful in summer!
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Based on Beer-Lambert's Law,
A = εcl ------(1)
where A = absorbance
ε = molar absorptivity
c = concentration
l = path length
Step 1: Calculate the concentration of the diluted Fe3+ standard
Use:
V1M1 = V2M2
M2 = V1M1/V2 = 10 ml*6.35*10⁻⁴M/55 ml = 1.154*10⁻⁴ M
Step 2 : Calculate the concentration of the sample solution
Based on equation (1) we have:
A(Fe3+) = ε(1.154*10⁻⁴)(1)
A(sample) = ε(C)(4.4)
It is given that the absorbances match under the given path length conditions, i.e.
ε(1.154*10⁻⁴)(1) = ε(C)(4.4)
C = 0.262*10⁻⁴ M
This is the concentration of Fe3+ in 100 ml of well water sample
Step 3: Calculate the concentration of Fe3+ in the original sample
Use V1M1 = V2M2
M1 = V2M2/V1 = 100 ml * 0.262*10⁻⁴ M/35 ml = 7.49*10⁻⁵M
Ans: Concentration of F3+ in the well water sample is 7.49*10⁻⁵M