Essay On Limiting Reactant

Two substances are mixed together. Explain how the observer could determine if this reaction is just a mixture or an actual chemical reaction. Give an example of two reactants that would form a mixture and two reactants that would form a chemical reaction. (Lesson 7)

An observer would see a series of different reactions if a chemical reaction was taking place. The first being is the substance a precipitate. Did a gas form from the mixing of the two substances. Is the color changing in any way. Was heat produced or absorbed from the reaction. Finally did the two substances product a new substance which is what the chemical reaction does.

Two examples of chemical reaction are:

Combining oxygen and sulfur will produce Sulfur Dioxide

S+O2------>SO2

Combining oxygen and iron will product Rust- which notes a color change
Fe+O2------>Fe2O3
Two reactants that form a mixture:
Combining sugar and water to make sugar water the substances remain intact through
C6H12O6+H2O----->C6H12O6
Combining salt and water to make a solution
NaCl----->Na+Cl
So in closing mixture can easily be separated back to original states, but chemical reactions produce new substances which cannot be reversed.

The concept of limiting reactant is a very important one in Chemistry. Explain what the concept of limiting reactant means and give an example of a limiting reactant everyday-life situation. (Lesson 8)

Limiting reactant means in chemistry we have a certain amount of one elements combined with two amounts of another element to product x certain amount of product. But because one is more than the other we will run out before we use up the same equal amounts of each elements.

Well lets say we are preparing to make a ham sandwich for lunch. We need 2 slices of bread and 3 slices of ham. The bread package contains 24 slices, the ham package contains roughly 18 slices of ham. So how many sandwiches can be made if we have one package of bread and one package of ham? In this case the limiting reactant would be the ham?

Example:

The chemistry equation would be balanced like so,

2 slices bread + 3 slices ham----> ham sandwich

The limiting reactant we would assume would be the ham. The calculation would show that we would need 2 packages of 18 slices of ham in order to have equal “react” amounts of 24 bread slices bread to 36 slices of ham to produce the ham

sandwiches.
The equation would look like such.
2 slices bread + 3 slices ham = 1 ham sandwich
{12 slices bread/1} {3 slices ham/2 slices bread}=6 ham sandwiches
So this calculation will show that 12 slices bread would require 3 slices of ham. But the bread package has 24 slices available, which would leave 12 slices left with all the ham used up. The ham will determine the amount of sandwiches that could be made from 1 package of ham. So the bread is the excess. So in order to use all of the bread we will need to have 2 packages of ham to 1 package of bread.
The equation of equal parts would be as such:
{24 slices bread/1}{3 slices ham/2 slices bread}=12 ham sandwiches