par 1.3 transition of phases

• Scheikunde
• Middelbare school
• mavo
• Leerjaar 3

today

discuss par. 1.3

check questions par 1.1 and 1.2

questions par. 1.3

paragraph 1.3

transition of phases

you will learn

• 3 phases and transition of phases
• convert  ^oC to K and vice versa
• difference between pure substance and mixture 
• interpret graph of a pure substance and mixture

transition of phase from solid to liquid?

From gas to liquid?

Phase of water at -20 degrees Celsius is?

If a substance, not water , melts, this will happen at......

1. 0 C
2. 100 C
3. 20 C
4. each substance has its own meltingpoint.

Alcohol has a meltingpoint of
and a boiling point of .
What is the phase of alcohol at

−114​0​​C

78​0​​C

120​C​​

Temperature scales

• degrees Celsius  (^oC)
• Kelvin (K)
• convert Kelvin to ^oC and vice versa
• 
  

20 degrees Celsius is ....... Kelvin

150 Kelvin is ....... degrees Celsius

pure substance and mixture

• pure substance : one single substance , made up of one type of molecules

• mixture : two of more substances mixed together, made up of different type of substance

examples

pure substance :

sugar, alcohol , destilled water

mixture : medicines, air, tapwater 

finding out if a substance is pure or a mixture

• prefrom this experiment : 

a pure substance has a melting point

a mixture has a melting range

a liquid starts to boil and temeperature slowly rises. This is a .....

1. pure substance
2. mixture

what is shown in the graph?

1. boiling point
2. melting range
3. boiling range
4. melting point

what is shown in the graph?

1. melting range
2. solidifying point
3. solidifying range
4. melting range

home work

read par. 1.3

do questions par. 1.3