Colegio San Agustin
Junior High School
Academic Year 2018-2019
PERFORMANCE TASK PHYSICAL SCIENCE
Name: ALEO FALE
Section: 11H
Submitted to: Mr. Albert A. Gutierrez
A. INTRODUCTION
One of the most important events happening in the universe is chemical reaction. According to
Helmenstine (2019), it is through chemical reactions that plants grow, produce fruit, and
become compost for new plants. In order for us to understand the complexities of these
chemical reactions, we need to understand stoichiometry. This report aims to explain concepts
and specific real-life application about the topic on chemical reactions and stoichiometry.
Specifically, it will show how to calculate the amount of substances used or produced in a
chemical reaction; the percent yield of a reaction; and to determine the limiting reactant in a
reaction and to identify the amount of product formed.
B. PROPANE GAS USED FOR COOKING
Cooking with gas provides more heat than using
electrical stove. During refinement process, propane is
extracted from crude oil and petroleum gas. Compared
to natural gas, propane is widely used because it has
higher BTU rating and it tends to heat faster and use less
fuel in cooking (WebstaurantStore, 2018). Propane is a
hydrocarbon that contains three atoms of carbon and eight atoms of hydrogen. It is also called
as an LP gas. Propane is commonly used for cooking because when it is exposed to oxygen it
will produce heat which we can use to cook our food. The type of reaction happening in this
event is called a complete combustion. A complete combustion happens when a reactant burns
in oxygen, and produces limited number of products. Commonly, when a hydrocarbon like
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propane burns oxygen, it will produce water and carbon dioxide. The balance equation for this
reaction is a follows:
C3H8 + 5 O2  3 CO2 + 4 H2O + heat.
Since the air (oxygen) surrounding the stove and a fuel source
the propane tank which then combine with the pre-existing heat
source of stove lighter to use its thermal energy to create fire,
which can be used for cooking, because of the heat produced.
The water produced will change into steam and the carbon
dioxide will be released back into the environment.
C. PROPANE PLUS OXYGEN YIELDS CARBON DIOXIDE PLUS WATER
C3H8 + 5 O2  3 CO2 + 4 H2O + heat.
Reactants
Reactants
Elements
Products
No. of
Atomic
Molecular
atoms
Mass
Mass
g/mol
(g/mol)
Total
C
3
12.01
36.03
H
8
1
8
O2
O
2
15.99
31.98
31.98 g/mol
Products
Elements
No. of
Atomic
Molecular
Total
atoms
Mass
Mass
g/mol
(g/mol)
C3H8
CO2
H2O
C
1
12.01
12.01
O
2
15.99
31.98
H
2
2
2
O
1
15.99
15.99
44.03 g/mol
43.99 g/mol
17.99 g/mol
2
D. IDENTIFYING LIMITING REACTANT, ACTUAL YIELD, PERCENT YIELD
Given: 40g of C3H8 and Actual yield - 23 g of CO2
1. Balanced Equation: C3H8 + 5 O2  3 CO2 + 4 H2O + heat.
2. Identifying the limiting reactant
40g of C3H8
X
31.96 g of O2
1 mol of C3H8
44.03 g/mol of C3H8
X
X
3 mol of CO2
1mol of C3H8
1 mol of O2
31.98 g/mol of O2
43.99 g/mol of CO2
1mol of CO2
X
3 mol of CO2
5 mol of O2
X
=
43.99 g/mol of CO2
1mol of CO2
119.89 g
=
26.394 g
Limiting
reactant
3. Percent yield
Percent yield =
Percent yield =
Actual yield
Theoretical yield
100
X
23 g of CO2
X
26.394 g of CO2
100
=
87.15 %
E. REFERENCES
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Helmenstine, A.M. (2019). 8 Reasons why chemical reactions are important. Chemistry
changes the universe. Thought co. Retrieved from: https://www.thoughtco.com/importanceof-chemical-reactions-604047
Propane Vs. Natural Gas. Comparing Cooking Fuels. (2018). WebstaurantStore. Retrieved
from: https://www.webstaurantstore.com/article/112/propane-vs-natural-gas.html
Propane Safety. (n.d.). Retrieved November 12, 2014, from http://cpadev.cyansolutions.com/sites/default/files/files/PropaneSafety_StorageHandling_E1.pdf
Reaction of Propane with Oxygen! (n.d.). Retrieved November 12, 2014, from
http://thecolt84.wordpress.com/2011/03/28/hello-world/
Propane, C3H8, Physical properties, safety, MSDS, enthalpy, material compatibility, gas
liquid equilibrium, density, viscosity, flammability, transport properties. (n.d.). Retrieved
November 12, 2014, from http://encyclopedia.airliquide.com/Encyclopedia.asp?GasID=53
Dimethylmethane. (n.d.). Retrieved November 12, 2014, from
http://www.chemspider.com/Chemical-Structure.6094.html
Physical Properties for Carbon Dioxide. (n.d.). Retrieved November 12, 2014, from
http://www.airproducts.com/products/Gases/gas-facts/physical-properties/physical-propertiescarbon-dioxide.aspx
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