Unit A: Section 1.0
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What does WHMIS stand for?
Workplace Hazardous Materials Information System
What is MSDS?
Identifies physical and chemical hazards associated with a product
What do Physical Properties describe?
They describe the physical appearance and composition of a substance
What are the common Physical properties
• Boiling point • Melting point • Freezing point • Malleability • Ductility • Colour • State • Solubility • Crystal formation • Conductivity • magentism
What do Chemical properties describe?
The reactivity of a substance
What are the common chemical properties?
• Ability to burn • Flash point • Behaviour in air • Reaction in water • Reaction with acids • Reaction with heat • Reaction to litmus paer
What is a flash point?
Temperature needed to ignite a flame
What happens if a substance undergoes a physical change?
It still has all the same properties and is reversible
What happens if a substance undergoes a chemical change?
A new substance is formed and it is irreversible
What are the 2 classifications of matter?
Pure substance or Mixture
What is a pure substance?
All the particles that make up the substance are chemically combined and identical
What are the 2 components of a pure substance?
Element and Compound
What is an element?
A pure substance that cannot be broken down into other substances and made of only one type of atom
What is a compound?
An group of elements that are chemically combined and in fixed proportions
What is a mixture?
A combination of pure substances that are not chemically combined and proportions can vary
What is a mechanical mixture/heterogeneous mixture?
When the different components are visible such as soil
What is a suspension?
A type of mechanical mixture where the components are in different states such as mud
What is a colloid?
The same thing as a suspension but the particles cannot be easily separated
What is a Solution or Homogeneous mixture?
One substance dissolved within another but it looks the same throughout
What is a chemical reaction?
A process that occurs when substances react to create different substance
What are some ways to preserve food?
Heating Freezing Salting Fermentation Smoking
What is Sterilization?
Any process that kills micro-organisms
How does freezing sterilize food?
The o-organisms that low temperature prevents the growth of micro-organisms that cause decay
How does salting sterilize food?
The salt draws the water out of the meat and the bacteria which kills them or inactivates them