compounds are homogeneous materials with definite composition which may be decomposed into two or...
TRANSCRIPT
COMPOUNDS are homogeneous materials with definite composition which may be decomposed into two or more simpler substances by chemical change.
ACIDS & BASES
ACIDS are characterized by:
a) Sour tasteb) Turns blue litmus
paper to redc) React with bases to
form salts & waterd) React w/ active
metals to produce hydrogen gas.
e) “burns” your skin: corrosive
f) pH value : 0 to 6.9
BASES (also ALKALI) characterized by:a) Turns red litmus paper
to blueb) Slippery and soapy feelc) Bitter or biting tasted) React with acids to form
salts and watere) Turns fats into soaps
f) pH value : 7.1-14
ELECTROLYSIS is a chemical process by which an electric current is applied into their constituent elements that changes the composition of the materials.
SOLUTIONS are homogeneous mixture that is composed of a solute and a solvent. The new
combination has only one phase.
SUSPENSIONS are heterogeneous mixtures that have the biggest particles.
COLLOIDS are heterogeneous mixture in which one substance is dispersed evenly throughout
another
Classify the following matter : Homogeneous, Heterogeneous,
Compound or Element
Cement
Dust free air
22 karat Gold bracelet
Pure NaCl
Al metal
Dry sugar + flour
Filtered Sea water
Na metal
Brass
Homogeneous mixture
Heterogeneous mixture
Homogeneous mixture
Compound
Element
Heterogeneous mixture
Homogeneous mixture
Element
Homogeneous mixture
DECANTATION is the separation of mixtures with different densities.
CHROMATOGRAPHY is the separation of components in a mixture based on the affinity for the solvent.
What method will you use to separate immiscible liquids? (Oil and water)
It can be separated using a SEPARATING FUNNEL. This apparatus allows the lower, more dense liquid to be drawn off at the bottom, leaving the less dense liquid in the funnel.
An older and less satisfactory technique is the process of DECANTING where the top layer is simply poured off.
Problem: Aquarium B has to be filled with some water samples brought from the coast. However, this sample is suspected to be contaminated with a dissolved solid and a dissolved liquid. If the water is not purified, it cannot be used by the fish.
Task: Obtain a clean sample of water and show the pollutants that were affecting the water.
Questions:What types of mixtures are observed in the aquarium?What is meant by physical means of separation? What is the difference with chemical means?
THE END…..