Answer:
<h2><u>Reason:</u></h2>
Catalyst is used as a very fine powder and larger pieces of iron are not used. This is because the surface area of catalyst needs to be large so that more of the surface is exposed to the substrate and more of the substrate is catalyzed.
<h2><u>Important Info:</u></h2>
=> Larger Pieces of Iron has a smaller surface area than the fine particles.
=> Larger the surface area of catalysts/enzymes , more will be the reaction rate and vice versa.
Hope this helped!
<h2>~AnonymousHelper1807</h2>
The final temperature of the mixture : 21.1° C
<h3>Further explanation </h3>
The law of conservation of energy can be applied to heat changes, i.e. the heat received / absorbed is the same as the heat released
Q in(gained) = Q out(lost)
Heat can be calculated using the formula:
Q = mc∆T
Q = heat, J
m = mass, g
c = specific heat, joules / g ° C
∆T = temperature difference, ° C / K
Q ethanol=Q water
mass ethanol=

mass water =

then the heat transfer :

1. Take 100ml of water as solvent and boil it few minutes.
2. Now add one tea spoon sugar, one tea spoon tea leaves and 50ml of milk. Here sugar, tea leaves and milk are solute.
3. Now boil it again for few minutes so that sugar will dissolves in solution as sugar is soluble in water
4. Now filter the solution. Collect the filtrate in cup. The insoluble tea leaves will be left behind as residue.
<span>11.2G is the answer to this problem.
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