Chromium

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CHEMISTRY PROJECT

• Chromium

Class 5E Name Ho Ka Yu Leung Shu
Ting Wong Yuen Ting Yip
Chi Chin
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BASIC INFORMATION

• Symbol Cr
• Atomic Number 24
• Name Origin From the Greek word chró_ma
• Obtained From Chromite
• Discovered By Nicholas Louis Vauquelin

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PROPERTIES

• a lustrous steel-gray color which takes a high
  polish
• hard and resistant to corrosion
• has a high melting point, stable crystalline
  structure, and moderate thermal expansion.
• All chromium compounds are colored.
• Chromium compounds are toxic.

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USE OF CHROMIUM IN OUR DAILY LIFE
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• Drilling Mud
• - prevent corrosion of steel under wet
  condition
• Laboratory Glassware
• - chromic acid is a powerful oxidizing agent
• Wood Preservative
• - protect wood from decay fungi, wood
  attacking insects

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• Metallurgy
• - Decorative chrome plating on a motorcycle
• Dye and Pigment
• - used for school bus in the US and Postal
  Service in Europe
• Tanning
• - stabilizes the leather by linking the
  collagen fibre

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HEALTH EFFECTS

• Shortages may cause heart conditions, disruptions
  of metabolisms and diabetes
• Uptake of chromium (III) can cause instance skin
  rashes
• Chromium (VI) in leather products can cause
  allergic reactions
• Breathing in chromium (VI) can cause nose
  irritations

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End