Unit D Lesson 5: Chemistry and Electricity
Completion requirements
Unit D Lesson 5: Chemistry and Electricity
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Learning Targets |
Big Question: How does chemistry relate to electricity?
Humans have a large amount of influence over the types and amounts of chemicals found in the environment.
Humans have a large amount of influence over the types and amounts of chemicals found in the environment.
At the end of this inquiry, you should be able to answer the following questions:
- What are chemical reactions that use electricity?
- What is galvanization and what is it used for?
- What is electroplating and what is it used for?
- What is electrolysis and what is it used for?
Pages 292 to 294 in your textbook will help you answer these questions about chemistry and electricity.
Introduction
Figure 1 – A shiny red spots car.
Figure 2 – An old, rusty car.
Electrolysis, Galvanization, and Electroplating
Have you ever wondered how the car in figure 1 keeps a shiny new look? Why does the car in figure 2 look like it has seen better days? As you look at the cars, you notice that one is new and one is old. What allows a car to keep its fresh-paint look? In today's world, it is common to see many older vehicles that look very new with no rust on them. Science has allowed us to improve our inventions.
Have you ever wondered how the car in figure 1 keeps a shiny new look? Why does the car in figure 2 look like it has seen better days? As you look at the cars, you notice that one is new and one is old. What allows a car to keep its fresh-paint look? In today's world, it is common to see many older vehicles that look very new with no rust on them. Science has allowed us to improve our inventions.
Galvanization
Electrochemistry is the study of electricity involving chemical reactions. In the automobile industry, cars are made of iron and steel that can rust easily when in contact with oxygen and moisture – and even faster if they are on roads where salt is used in winter!
However, if you galvanize (coat he base metals with zinc), you can prevent the iron and steel blend from coming in contact with the elements (oxygen and moisture) and, therefore, prevent rust from occurring. How does galvanization occur? The process, called dipping, is like getting a chocolate dipped ice cream cone.
Electrochemistry is the study of electricity involving chemical reactions. In the automobile industry, cars are made of iron and steel that can rust easily when in contact with oxygen and moisture – and even faster if they are on roads where salt is used in winter!
However, if you galvanize (coat he base metals with zinc), you can prevent the iron and steel blend from coming in contact with the elements (oxygen and moisture) and, therefore, prevent rust from occurring. How does galvanization occur? The process, called dipping, is like getting a chocolate dipped ice cream cone.
Watch
Watch how galvanization works as if by magic in
"How to Galvanize Metal (for rust protection)".
Can you galvanize at home? Watch
"Turn pennies silver and gold (Chemistry Trick)" to see how.
Electroplating
When one form of metal is coated onto another metal, the process is called electroplating. This is done using two electrodes and an electrolyte to allow metallic ions from the electrolyte to be deposited onto an object. Electricity is needed for this chemical reaction; therefore, we call it electroplating. Both galvanization and electroplating involve electrochemistry but are used for two different practical applications. Galvanization prolongs a vehicle’s paint job and electroplating allows us to coat objects metals that would either be too expensive or too weak to be used to construct the whole object from.
When one form of metal is coated onto another metal, the process is called electroplating. This is done using two electrodes and an electrolyte to allow metallic ions from the electrolyte to be deposited onto an object. Electricity is needed for this chemical reaction; therefore, we call it electroplating. Both galvanization and electroplating involve electrochemistry but are used for two different practical applications. Galvanization prolongs a vehicle’s paint job and electroplating allows us to coat objects metals that would either be too expensive or too weak to be used to construct the whole object from.
Electroplating is used in jewellery. Gold and silver are not strong metals to keep their shape compared to iron or nickel, and gold and silver are expensive. By electroplating jewellery with gold and using a stronger and cheaper metal beneath, beautiful strong pieces of jewellery are available for a fraction of the cost of solid gold or silver pieces. This is why you hear the term 10-karat gold or 14-karat gold, which refers to the amount of real gold in the piece of jewellery. Most of the metal is under the electroplated gold.
Watch
Electroplating is very common in the creation of jewelery. But is it used for anything else? Learn more about electroplating by watching "Electroplating".
Electrolysis
Another example of electrochemistry is electrolysis, which uses electricity to separate chemical compounds into its elements. A common example is breaking up water. Electricity separates the water into oxygen gas and hydrogen gas. When these gases unite again, a major explosion occurs and huge amounts of energy are produced. Rocket ships use this technique to obtain the energy they need for lift off.
Electrolysis is used in many industrial process that require a metal to be removed from non-metallic compounds, such as refining ores.
Another example of electrochemistry is electrolysis, which uses electricity to separate chemical compounds into its elements. A common example is breaking up water. Electricity separates the water into oxygen gas and hydrogen gas. When these gases unite again, a major explosion occurs and huge amounts of energy are produced. Rocket ships use this technique to obtain the energy they need for lift off.
Electrolysis is used in many industrial process that require a metal to be removed from non-metallic compounds, such as refining ores.
Watch
Electrolysis can be a blast! To see why, check out
"Hydrogen and Oxygen from Water".
Try It!
Practice Worksheet: Electrochemistry Definitions
- DOWNLOAD this practice worksheet (S9_UD_S1_L5_electrochemistry) worksheet. If you prefer to use a Google Drive or PDF version of the worksheet, click here.
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Complete the worksheet.
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When you are satisfied with your responses you can check your work by clicking on the "SUGGESTED ANSWERS" button below.
Wait! Don't view the suggested answers first. This practice work is not for marks, it is meant to help you check your understanding. Check the answers AFTER doing the questions! Keep the practice worksheet for study purposes. If you don't understand something, contact your teacher!
Watch
Did you know that electricity is sometimes used to paint vehicles and strangely-shaped objects? Electrostatic electricity is used to paint a pipe in the following video: "Electrostatic Painting". Powdered paint shoots out of a gun and becomes
negatively charged due to the friction. Then, it is attracted to the neutral pipe. This is the third law of charges: charged objects are attracted to neutral objects. In some cases, painters will use electricity to positively charge the object that
is being painted – this creates and even stronger attraction of paint to object, and increases painting efficiency even more.