KISI-KISI UTS 7 RSBI

1. To mention prefixes in SI and their multiples
2. To identify the SI symbols and units for length, mass, time, and volume
3. To convert several SI units
4. To explain the definition of measurement
5. To Compare Celsius scale with the other temperature scale
6. To define standard measurement
7. Explain definition of element
8. Write name and symbol of element
9. Write simple chemical formula and their name
10. Mention example of compound and their chemistry formula
11. Make different characteristic between element, compound, and mixture base on experiment
12. Make a simple scheme of classification matter based on matters characteristic (element, compound, and mixture)
13. Classify the thing that commonly see in daily life into homogeneous mixture and heterogeneous mixture

What are Mixtures and Solutions?

A MIXTURE is a combination of two or more substances that are not chemically united and do not exist in fixed proportions to each other. Most natural substances are mixtures.

In the graphic on the left there are four substances - water, alcohol, oil, and food color dye.




MIXTURES
- A mixture can be physically separated into pure compounds or elements.
- Just about everything that you can think of is probably a mixture. Even the purest of materials still contain other compounds as impurities.
- Mixtures may exhibit a changing set of physical properties.
For example, mixture of alcohol and water boils over a range of temperatures.


PURE COMPOUNDS
- A pure compound has a constant composition with fixed ratios of elements.
- Although it is almost physically impossible to isolate absolutely pure substances, a substance is said to be pure if no impurities can be detected using the best available analytical techniques.
- Physical properties such as boiling point or melting point of pure substances are invariant.For example, pure water boils at 100 degrees C

MIXTURE SEPARATION

Separation Techniques

Deal with the separation of mixtures to enhance purity of substances
This is very important because most substances are needed in their pure state.

Some Types of Separation Techniques

Filtration
This is a technique used to separate mixtures of an insoluble solid and a liquid.



Examples of Mixtures You Can Separate Using Filtration
- Sand and water
- Broken glass and water
- Chalk suspensions and water

Chromatography

Chromatography is the separation technique used to separate soluble substances using a media and a solvent.
It is mostly applied in identifying mixtures that are coloured or pigments.

Types of Chromatography
- Radial chromatography
- Ascending chromatography
- Descending chromatography

Radial Chromatography
In this type of chromatography, as the pigment separates, the different colours move outwards.

Radial Chromatogram



Ascending Chromatography
The solvent moves upwards on the separating media




Descending Chromatography
The solvent moves downwards on the separating media.




Distillation

This is the separation technique where two miscible liquids are separated.
It is made possible due to the fact that each liquid has its unique boiling point.

Types of Distillation
- Simple distillation
- Fractional distillation

Simple Distillation
This is a technique used to separate a mixture of a soluble substance and a solvent.
E.g salt and water



Fractional distillation

This is the technique used to separate a mixture of two miscible liquids with different boiling points.E.g water and ethanol
The boiling point for water is 100 while for ethanol it is 78.

Fractional Distillation Demonstration




Questions
1. What is a mixture?
2. Give three ways of separating a mixture.
3. What kind of mixtures can you separate using the filtration method?
4. Give an example of a mixture you can separate using the fractional distillation method.


Answers
1. It is a substance made up of two or more substances which are physically combined.
2. Filtration, Chromatography and Distillation.
3. Mixtures of an insoluble substance and a liquid.
4. Ethanol and water.

EXERCISE 1.2

1. what the meaning of element? mention the example!

2. what the meaning of compound? mention the example!

3. Mention the kind of mixture and explain it!

4. Write the symbol of elements below :
a. Sodium
b. Iron
c. phosporus
d. helium
e. silver
f. gold

5. Mention the properties of compound!

6. Mention the ways to separate mixtures!

7. explain the difference between metal and non-metals elements and mention the example of each other!

EXERCISE 1.1

1. Which of following substance are elements, compounds, and mixture :

a. Ammonia
b. air
c. Chlorine
d. methane
e. Radium
f. sea water
g. Silicon

2. What is elements that maked use in things maker follow:
a. gold bracelet
b. advertisement lamp
c. drink can
d. air ballon
e. battery
f. wound medicine


3. Write the symbols, atomic number, mass number, the amount of proton-netron- electron, and depict nucleus, of the following elements :
a. Hydrogen
b. Mangaan
c. Chlorine
d. Mercury
e. Aluminium
f. Crypton

4. Explain the differences between compounds and mixture !(3 kinds)


5. Name the elements of the following compounds and mention the number of atoms in each molecule :
a. Mg(OH)2
b. CH3COOH
c. KMnO4
d. 2 H2SO4

6. a. Write and explain procedure that used to Purifying water.
b. You have to shake syrupe medicines before dringking. What is the aim of shaking? Explain!

7. Look at periodic table! Mention elements that present in :
a.noble gas group
b.alkali group