Practical
What is Energy?
The ability to do work
In our experiment the match represented what part in a combustion reaction
the necessary activation energy
describe how much energy is transferred from one object to another when the energy transfer occurs.
since energy cannot be created nor destroyed, any energy transferred from one object to another transfers
give an example of a carbohydrate that is not a cheeto, also an example of a fat that is not a nut
answers will vary
when plotting points on a graph you first move _______ on the _______, then __________ on the ___________, then make a plot point
horizontally on the x-axis, then vertically on the y-axis
give a detailed example of energy flowing through a system
heat from stove to pot to water to noodles to surroundings (outside of the system)
why wouldn't the cashew combust and what could we have done to help combustion to happen?
The match did not provide enough activation energy for the reaction to proceed, if we would have liked to see this reaction proceed we could have gotten a heat source that would have provided a higher temperature of heat.
Describe the potential energy of a chemical reaction and how the energy is accessed.
Potential energy is found in the bonds of molecules, and when a reaction occurs, the energy is accessed. Sometimes energy is needed to get the reaction started. This is referred to as activation energy.
explain what smoke point is
the smoke point is the temperature at which an oil will go through a phase change from aqueous solution to gas. At this point the oil becomes toxic
When we make graphs in science the y axis reserved for.......
what is being measured
what type of energy is found in our food and fuels, and where is it stored?
potential and it is found in the bonds of the molecules
describe the energy transfers including type of energy and transformations within the experiment that we did
The thermal energy from the match acted as our activation energy, which was transferred to our fuel source, the cheeto. The cheeto burned and released energy in an exothermic reaction and the energy was transferred to the water and raised it's temperature
A reaction takes place in a closed system in which the temperature drops and condensation forms on the outside of the system. This reaction can be described as–
a reaction that absorbs energy from the surroundings.
Define a system
a system is a set of things we define that are interacting with one another where in entropy occurs and heat is exchanged
describe the difference between a graph and data table. draw a picture of both on my board.
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how do we release the energy from our food and fuels?
combustion must occur, we must add activation energy to our fuel to break the chemical bonds and then a large amount of energy will be released
explain the difference between the way the cheeto burned and the way that the cashew burned, and how this relates to energy in our bodies when we digest these two food items
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A strip of magnesium is placed into a test tube with hydrochloric acid to form magnesium chloride and hydrogen. The total mass of the reactants is measured to be 12 g. After the reaction is complete, the mass of the system is 11.8 g. What happened to the rest of the mass?
It left the system as hydrogen gas.
discuss one tool we use to measure energy and the units that we measure energy in (there are two)
thermometer, calories, joules
given the following data draw a diagram of what the graph of the line may look like:
day 1 : 2cm day 2: 4cm day 3: 8 cm day
4: 16cm day 5: 32cm
the line will be an exponential curve
Draw a model of each molecule and use that drawing to explain the way energy burns in both a carbo and a fat (you must prove it by explaining the molecular structure of each molecule from your drawing)
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What are the products of combustion based on what you saw? (When things combust what is made? there are a few)
water heat light
draw an energy diagram for the melting of ice
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What is a molecule? It may help you to draw it out and explain it
a molecule is made up of multiple atoms which are made up of protons neutrons and electrons all held to gether by bonds
Draw an example of both an exothermic and endothermic reacttion graph and explain what is happening in each type of reaction.
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