Lesson 2: Elements, Compounds and Mixtures

This is the Periodic table:

All Metals are conductors of electricity.
Non-metals are generally non-conductors of electricity. * Carbon and Silicon are exceptions

All matter can conduct heat. However, it depends on how fast or slow it does.

Metalloids have physical properties that resembles metals and chemical reactions that resemble non-metals.

Groups must always be in roman numerals.

*When answering questions*

Name the elements --> state full name
Identify Elements --> Chemical symbols/full name

Rare gases can be called inert gases, noble gases, group 8, 18 or 0.

*Make sure that chemical symbols are properly written in upper and lower case.

Examples of compounds:
water, carbon dioxide, carbon monoxide, hydrogen chloride, calcium carbonate

Examples of mixture:
steel, stainless steel, brass, froze, air, muddy water, seawater, mineral water

Lesson 1: Elements, Compounds and Mixtures

Elements:
-cannot be split into 2 or more simpler substances, which have identifiable characteristics social to themselves
-can be grouped into 3 groups: metals, non-metals and metalloids due to their properties
-are made up of tiny particles called atoms
-Metals are ductile

Compounds:
-always has chemical reaction
-2 or more elements that make a new substance
-can only be broken down into simpler substances by electricity as well as chemical reactions

Mixtures:
-2 or more substances that are mixed together but not chemically combined
-no chemical reactions
-physically combined
-no fixed ratio/ proportion
-does not lose its own characteristics
eg.         salt+water
             =salty water --> still salty, still wet
-separable into components by physical methods

* In science, sometimes, specific terms are required. However, in some case, more general terms are appropriate.
eg.
    2 or more elements that are chemically combined make a compound.
    2 or more substances that are not chemically combined make a mixture.