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Kids Quiz


									Pure Substances & Water

Heterogeneous               Homogeneous

                Solutions            Pure substances
A Pure Substance:

• is always homogeneous
• is made of one kind of
  particle, different from the
  particles of other pure
• has the same properties no
  matter where in the world it
  is found
Pure Substances
Water = Pure Substance?
Q: How much of the human body is
made up of water?

1: 50%
2: 70%
3: 90%

A: 70% of the human body is made up of water.
Water makes up about 50% of our blood and 25% of our bones.
Q: How much of the earth’s surface is covered by water?

1: 20%
2: 50%
3: 70%

   A: About 70% of the earth’s surface is covered
   by oceans and lakes.
Q: How much of the world’s water
is fresh (non-salty) water?

1: 3%
2: 53%
3: 70%

A: Only 3% the world’s water is freshwater. The remaining 97%
of the world’s water is too salty for humans and most animals
and plants to use.
Q: How much of the world’s freshwater supply is located in

1: 3%
2: 10%
3: 20%

    A: About 20% or one-fifth of the world’s freshwater
    is found in Canada’s rivers, lakes, groundwater,
    ice, and snow. – We account for 0.5% of the world’s population
Q: How much water does a Canadian typically use
each day?

1: 90 litres
2: 192 litres
3: 326 litres

 A: 326 litres a day or about a bath tub full of water. About
 10% of this is used for drinking, cooking and dishwashing.
 The remaining 90% is used for flushing the toilet, showers
 and baths, and laundry.
Q: How much water does someone living in rural areas
of Africa typically use?

1: Less than 20 litres
2: About 50 litres
3: More than 100 litres

 A: In many parts of rural Africa, it is common for people to use
 only 10-20 litres of water a day, mainly because they have to
 carry it over long distances. In the United States people use
 about 425 litres, in Sweden 200 litres, and in France 150 litres.
Q: How many people living in the world do not
have access to clean drinking water?

1: 100 million (about three times the population of Canada)
2: 500 million (about 15 times the population of Canada)
3: 1.1 billion (about 30 times the population of Canada)

 A: 1.1 billion people, about 20% of the world’s population,
 have to rely on unsafe sources of drinking water such as
 polluted rivers and lakes that cause many health problems.
 Most live in developing regions such as Africa, Asia,
 and Latin America.
We’ve learned that only 3% of Earth’s water is fresh …

                      Are there ways for us to
                      separate solutes (like salt)
                      from water??

   Stay tuned for tomorrow’s class …

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