Please enable JavaScript.
Coggle requires JavaScript to display documents.
nature of matter and experimental techniques (Jack) (measurement (thermal…
nature of matter and experimental techniques (Jack)
diffusion
Diffusion occurs when particles spread and it always from high concentration to low concentrated .The particles are free to move
type of graph
Scatter plot and line of best f
Pie Chart
Line graph
Bar chart
be careful
• Plot graph in proper scale – made a large drawing, using the space provided.
• Each smallest scale represents the same amount.
• Label X-axis and Y-axis, including name and unit.
• Use “x” to represent each data point.
• Draw the line of best fit using straight line or smooth curve.
• Gradient/slope of the curve represents the rate of changing
measurement
thermal-meter temperature(c)
electronic balance mass(g)
burette volume (cm3)
measuring cylinder volume of liquid (cm3)
pipette volume (cm3)
stopwatch time (second)
density =mass/volume
three state and change state
liqudi
to solid is call freezing
to gas is call evaporation
gas
to solid is call sublimation
to liquid is call condensation
solid
to liquid is call melting
to gas is call sublimation
method of purification
A pure substance has no particles of any other substance mixed with it.
Crystallisation a solute from a Solution
Simple distillation a solvent from a solution
Fractional distillation liquids from each other
Filtration a solid from a liquid
Solvent extraction two immisible liquid
Paper chromatography mixture of colors
Filtration
Filtration separates a solid from a liquid.
(Example – separating sand from water.)
Evaporation
(Example – to obtain salt from sea water)
Crystallisation obtains solids from their solutions by letting crystals form. It works because soluble solids tend to be less soluble at lower temperature
Simple distillation Simple distillation obtains the solvent from a solution. (Example – to obtain water from sea
water)
Fractional distillation
Fractional distillation separates a mixture of liquids from each other
Solvent extraction
Mixtures of two immiscible liquids can be separated if the mixture is placed in a separating
funnel and allowed to stand. The liquids separate into different layers (Example – to separate the oil and water)
Paper chromatography can be used to separate a mixture of two or more dissolved substances.
(Example - to find out how many different dyes there are in black ink)
Rf =distance move by substance/distance move by solvent from
Important points for paper chromatography
The base line must be drawn using pencil, if not, the line can also be moved by the solvent.
When dip the paper in the solvent, the level of the solvent must start below the sample.
therwise, the sample will dissolve in the solvent directly rather than move up with the solvent.
A locating agent is used to produce colored spots for the colorless sample. :
The retention factor (Rf value) is used to identify the substance.
criteria of purity
A pure substance has a definite melting point and boiling point.
When a substance contains an impurity:its melting point falls and its boiling point rises.
o it melts and boils over a range of temperatures, not sharply.