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http://www.youtube.com/watch?v=Xi3oI_mGOHQ&feature=related
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Gymnastics
So the link…
• What do weight lifting, gymnastics and
Chemistry have in common?
Chemistry of chalk and MgCO3,
Weightlifting and the link to
chemistry
The lifters use chalk on their
hands to aid gripping the bar and
to remove moisture, which could
cause the bar to slip.
Chalk, a naturally occurring or man-made substance, is
engulfed with chemistry and it is here that a link between
chemistry and weightlifting can be found.
Chalk in sport
Lawn tennis – line boundaries of court
When the ball hits a boundary line it makes a cloud of
dust. Natural chalk has mostly been replaced with
titanium oxide now in tennis.
Gymnastics & rock climbing – stop slipping
• Chalk is applied to hands, arms & legs to stop slipping
and absorb moisture.
• Natural chalk has mostly been replaced with magnesium
carbonate here.
Other uses of chalk
Small amount found in tooth paste
Implements to write with on black boards or for
pavement drawings
The characteristics of chalk
Chalk is:
• A soft solid
• White
• It can also be found naturally as red in colour
Natural chalk is formed in the ground
and is:
• Porous sedimentary rock – can hold
water
• A form of limestone
• Composed of the mineral calcite
Man-made chalk
Natural chalk has widely been replaced with a man-made
chalk called magnesium carbonate.
Draw a dot and cross diagram and describe the bonding.
What are the properties?
It has similar characteristics to chalk in that it is a white,
soft solid.
The empirical formula of magnesium carbonate is MgCO3.
Magnesium carbonate, although used in sport, also has a
range of other uses which include being used in:
• Flooring
• Fireproofing
• Fire extinguishing
• Cosmetics
• Dusting powder
• Drying agents
• Laxatives for loosening bowels