Elements, Compounds, Mixtures Flashcards
What is an Element?
An element is a pure substance that cannot be split up into 2 or more simpler substances by chemical processes or by electricity
Properties of Metals
Shiny appearance
Good conductors of heat
High melting/boiling point (except Na, K and Hg)
Properties of Non-Metals
Dull appearance (if solid)
Poor conductors of heat (except diamond and graphite)
Low melting/boiling point (except C and Si)
What is an Atom?
Smallest particles of an element
What is a Molecule?
A group of 2 or more atoms that are chemically combined
What are Monoatomic Elements?
Elements that exist as individual atoms
Names of 2 atom, 3 atom and 4 or more atom
Diatomic
Triatomic
Polyatomic
What is a Compound?
A compound is a pure substance that is made up of 2 or more elements chemically combined in a fixed ratio
How are Compounds different from their Constituent Elements?
Physical and chemical properties of compounds are very different from its constituent elements
What is a Mixture?
Mixtures are formed when 2 or more substances are added together without chemical bonds being formed
Difference between Compounds and Mixtures in terms of Separation
Mixture: Components of a mixture can be separated by physical methods
Compounds: Elements in a compound can only be separated by chemical reactions or using electricity
Difference between Compounds and Mixtures in terms of Properties
Mixture: The chemical properties of a mixture are the same as its components
Compounds: Physical and chemical properties of compound are different from the elements in the compound
Difference between Compounds and Mixtures in terms of Energy Change
Mixture: Little/no energy change (no chemical reaction when mixture forms)
Compound: Energy change (chemical reaction takes place when compound forms)
Difference between Compounds and Mixtures in terms of Composition
Mixture: Components can be mixed in any proportion
Compound: Elements in a compound always combined in fixed proportions
