UNIT 2 - Elements
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What are elements?
The building blocks of matter
What is the purpose of chemical symbols?
To describe all elements using letters from their Greek or Latin names
How is each element represented in terms of chemical symbols?
By the first letter of its name or by the first two letters of its name
What is the format for writing chemical symbols?
The first letter is capitalized and the second letter is lowercase
What are physical properties of elements?
The appearance of a substance (e.g., colour)
What are chemical properties of elements?
Substance’s ability to chemically react with other substances to form new products
What are the two main classifications of elements?
Metals and Non-metals
What properties do metals typically have?
• Lustre: Shiny • Malleability: Malleable • Ductility: Ductile • Conductibility: Good conductors of heat and electricity • State: Solid at room temperature (except mercury) • Density: Usually denser than nonmetals • Reactivity: Active metals react with acid, and very active metals react with water
What properties do non-metals typically have?
• Lustre: Dull • Malleability: Likely to be brittle or shatter when struck • Boiling and melting point: Usually lower than metals • State: Often gases at room temperature • Conductibility: Poor conductors of heat and electricity
What are semimetals/metalloids?
Elements that share some properties with metals and some properties of nonmetals
What properties do semimetals/metalloids typically have?
• Lustre: Shiny • State: Solid at room temperature • Conductibility: Poor conductors of heat • Ductility/Malleability: Likely to be brittle or shatter when struck
Fill in the blank: The first letter of a chemical symbol is always _______ and the second letter is _______.
capitalized, lowercase
True or False: Most elements are non-metals.
False