Purpose
After completing this activity you will
be able to calculate mass-mass relationships in chemical reactions and identify
limiting reactants. You will also develop
some skills needed to include formulas in Excel spreadsheets and to construct
graphs with trendlines (or best fit lines).
Activity
a. grams of nitrogen
b. moles of nitrogen
c. grams of hydrogen
d. moles of hydrogen
e. moles of ammonia
based on N2
f. moles of ammonia
based on H2
g. limiting
reactant
h. moles of ammonia
based on limiting reactant
i. grams of ammonia
based on limiting reactant
j. grams of excess
reactant
3.
Construct a graph (scatter plot) that compares grams of
hydrogen vs. grams of ammonia produced.
Don’t include the points that show the mass of ammonia is not
changing. In this graph you will
include a trendline. After you have
constructed your graph place the curser on one of the data points and right
click the mouse. Select “add trendline”
from the menu. For “type” select
linear. Then click on the “options”
tab. Select “display equation on chart”
and “OK.”
4.
Construct a second graph that compares moles of hydrogen
used to moles of ammonia produced.
Again, don’t include the points that show the mass of ammonia is not
changing and include a trendline and equation.
Conclusion
1.
In your own words define the terms “limiting reactant” and
“reactant in excess.”
2.
In either graph what is happening at the points where the
slope remains zero?
3.
The linear regression (trendline) equations for the graphs
show that the y-intercept is zero. Explain.
4.
In the equation for graph 1, the slope equals 5.61.
a.
What is the unit of measurement associated with this
number?
b.
What does this number represent?
5.
What is the correct unit of measurement for the slope in
the equation for graph 2?
6.
How are the slopes of the lines in graph 1 and graph 2
related?