Chemistry - chapter 1

Classification of matter

• Matters : anything that occupies space and has mass
• physical state: liquid-solid-gas
• Gas State : No fixed volume or shape
• :Take the shape and volume of the container
• :their molecules are far apart and move fast
• liquid state: has distinct volume
• :no specific shape
• :can not be compressed
• :molecules are closed to each other
• Solid state: has definite shape and volume
• : rigid in shape
• : can not be compressed
• :molecules are held close to each other

According to its composition

according to its composition

• Elements : 1-building blocks of elements are Atom 2- the same type of elements combine to form molecules
• Compound : 1- form due to interaction of two or more elements

Elements

Compound

Mixture

• 1- A combination of two or more substance
• a) heterogeneous mixture
• • mixture does not have uniform composition
• • consist of two phases - solid, oil , water
• b) homogeneous mixture ( Solution )
• • every part keeps its properties
• • consist of a single phase Like > air , salt dissolved in H2O

Physical & chemical properties

• a) Physical properties
• • it is the one that can be measured or observed without changing the composition or identity of substance . Like > color , m.p , b.p , state of matter .
• Extensive properties - only depends on the amount of matter like > mass , volume , length .
• intensive properties - only depends on the type of matter , not the amount like > state of matter , color , melting point , boiling point
• b) Chemical properties
• • is the tendency of a substance to undergo a particular chemical reaction like > flammability , reactivity towards acids