Grade 10 Chemistry ? Cluster 2

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Grade 10 Chemistry ? Cluster 2 Chemistry in
Action

• Cultural and Historical Applications of Acid
  Chemistry

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Manitoba Curriculum Outcomes

• Cluster 0- Overall Skills and Attitudes
• S2-0-8d Describe examples of how technologies
  have evolved in response to changing needs and
  scientific advances
• S2-0-8e Discuss how peoples of various cultures
  have contributed to the development of science
  and technology.
• S2-0-9a Appreciate and respect that science and
  technology have evolved from different views held
  by women and men from a variety of societies and
  cultural backgrounds.
• Cluster 4 Chemistry in Action
• S2-2-09 Discuss the occurrence of acids and bases
  in biological systems, industrial processes, and
  domestic applications.
• Purpose Intent - The goal of this lesson is to
  
• 1. reveal a variety of cultural or historical
  views of the understanding of acids and bases .
• 2. challenge students to critically think, read,
  and write in the field of chemistry.

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Lesson Overview

• Teacher Notes
• Teachers should adjust and adapt the information
  and discussion questions in order to challenge
  their specific students to think, read, write,
  and discuss the relevant issues. As the main
  goal of this lesson is to reveal a variety of
  historical and/or cultural views of acid
  chemistry teachers should avoid focusing on the
  details of chemical formulas of acid chemistry.
  The presentations lack of scientific content is
  an intended omission.
• students often learn science from one perspective
  only, not realizing that the evidence-theory
  connection of all science is evident in the
  thoughtful and purposeful thinking of all
  cultures.
• Science must be presented in a manner that honors
  the thoughtful reasoning evident in all peoples.
  This is just not affirming the cultural diversity
  of the marginalized, but also helping the
  dominant culture to realize that other cultures
  are equally able to reason.
• Last two points Adapted from Prof. Elizabeth
  McKinley (University of Auckland)

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Lesson Structure

• The lesson includes TWO examples of how acids and
  bases have been thoughtfully understood and/or
  utilized in a variety of cultures and traditional
  belief systems

1. Acidic Lichen in the lives of the Inuvialuit
Gwichin of Northern NWT Yukon 2. How acidity
may provide a clue as to the health benefits of
the traditional Chinese diet?
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Acid Chemistry and the Inuvialuit Gwichin of
Northern NWT Yukon

• Caribou and Lichen

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Hallway of Aklavik School
NOTE Caribou have been, and continue to be,
central to the lives of the people of Aklavik
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Inuvialuit Gwichin of Northern NWT Yukon

• Recognized that the migration route of caribou
  followed mountain valleys and corridors.
• Migration of caribou is influenced by lichen
  abundance.
• One lichen today is called caribou moss
  Cladina rangiferina

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What does all this have to do with Acids?

• 1. Migration of Caribou
• Lichens are very acidic and most are not
  consumable
• Cladina rangiferina is not as acidic as other
  lichens and therefore palatable for caribou
• Migration of Caribou are determined by the
  growing seasons of the Cladina rangiferina

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• Yukon NWT has TONS of lichens but not all
  preferred

• Hard to distinguish between them by appearance

Not as preferred by caribou
most preferred by caribou
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What does all this have to do with Acids?

• 2. Colorant for clothes
• Acidic stomach contents of caribou (with lichen)
  used to alter colours of plants for dyes dark
  to light colours
• Plant dyes behave like indicators
• soapberries used to alter colour of plants
• - especially flowers - for dyes- light to dark
  colours

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Example of Colorants
BUTwhen certain material behave like indicators
and turn yellow in the presence of an acid of a
specific pH (lichen contents of caribou stomach)
This color is not found anywhere in nature in
Yukon NWT
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Traditional Chinese Medicine

• Yin and Yang of Fad Diets?

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Yin and Yang foods

• Traditional Chinese beliefs include two opposing
  principles Yin and Yang which regulate life
• this extends and influences many Asian diets as
  there is a belief that some foods are Hot (yang)
  or Cold (yin)
• It is believed that these foods (Hot/yang
  Cold/yin) need to be consumed in balance for a
  healthy diet

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• HOT FOODS
• believed to raise body heat and create tension
• Beef, chicken, eggs, mutton

• COLD FOODS
• believed to cool body heat and reduce tension
• Many vegetables

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Neutral foods

• are believed to contain equal parts yin and yang
  and therefore neither reduce or increase body
  temperature
• Brown rice, wheat, beans, some kinds of nuts

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Traditional Chinese Medicine

• Recent studies in diet have aimed to investigate
  the scientific merit of the traditional Hot/Cold
  Chinese diet.
• Some recent studies have found that many
• hot foods are acid forming foods and result in
  lower internal pH of the body (detected in urine
  samples)
• As a result minerals from bones leach into the
  body to act as a buffer to control acidity
  contributing to Osteoporosis
• Lower internal pH has been linked to many other
  diseases
• Breast cancer, high blood pressure, heart
  disease, diabetes, etc
• cold foods are alkaline forming foods and
  contribute to a more alkaline internal pH
• An alkaline internal pH reduces risk of many
  diseases

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Conclusion links between Traditional Chinese
Medicine and recent science research

• it is accepted that human health is dependant on
  an internal acid-base balance
• therefore there is growing interest and support
  for further research regarding the Hot/Cold diet
• Example ? how it is correlated with acid forming
  and alkaline forming foods
• other aspects of traditional Chinese medicine are
  also becoming the focus of increasing research

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Discussion Questions Extension Activities

• Acid Chemistry and the Inuvialuit Gwichin of
  Northern NWT Yukon
• Note how the role of the lichen in the migration
  of the caribou and the uses of the lichen as a
  colorant is solely based upon its specific acidic
  properties.
• Research to find how other cultures have made
  sense, applied, or utilized acids and/or bases.
• Example How Aboriginal peoples found a treatment
  for scurvy (using ascorbic acid)
• Yin and Yang of Fad Diets?
• Many immigrants of Asian decent may still
  understand or integrate principles of Hot and
  Cold foods into their personal diets. Find and
  interview some of these people to give you a
  fuller understanding.
• Note Remember it is only current research that
  is showing a possible link between acid/alkaline
  forming foods and Hot/Cold foods. Most of these
  people will not explain or discuss their diets
  using acid/alkaline terminology or understanding.
  
• Research the Mediterranean diet which is
  commonly regarded to be one of the healthiest
  diets in the world. What principles about the
  Mediterranean diet are in sync with concepts
  discussed in this presentation?