User:Liane23

Science 6:

Lesson 1 :

A combination of two or more substances that are not chemically combined is called a mixture.Mixture can be solid,liquid or gas.

A Solution is a Homogeneous mixture is a single phase mixture and cannot be identify or distunguished.

Example of a homogeneaous mixture:alloy,air and rubbing alcohol.

Water is the natural solvent

Solid is a solute

Lesson 2:

Factors that affect how a solute gets dissolved in a solvent:

1.Stirring or shaking -dissolved faster by solute,This happens beacause stirring caused the surface of each tiny particles of substances and other to be pulled away.

2.Crushing-the solid makes it dissolves faster.

3.Heat Energy-as motion of solute and solvent increase.

Lesson 3:

Miscble solution:is when two liquids do is form a new liquids.

Immiscble's solution:is when two liquids do not mix together instead form layers.

Miscble solutions is a Homogeneous mixture and it is uniform.

Immiscble solutions is a Heterogeneous mixture and it is non-uniform.

Lesson 4:

Solutions are Homogeneous mixture:

Solutions are combinations of two or more substances forming a homogeneous mixture.

Solutions are common at home.We use it in your everyday activities.

Some are used as preservatives & condiments like soy-sauce and vinegar.

Some solutions are used for cleaning and disinfecting like bleach and alcohol.

Other solutions are used for personal hygiene like mouthwash.

Solute is the substance being dissolved.

Solvent is the substance that dissolves the solute.

Lesson 5:

Thera are factors that affects the conditions of dissolving materials like stirring of mixture,size of particles and temparature of solvent.

Stirring a solute into a solvent speeds up the rate of dissolving beacause it helps distributes the solute particles throughout the solvent.

ex.When you add sugar to iced tea and then stir the tea,the sugar will dissolve faster.

Temparature allows the solvent molecules to more effectively break apart the solute molecules that are held together by inter molecular attractions.

ex.When you dissolved powdered milk using hot water

Particle size a thrid factor that affects the rate of dissolving the size of solute particles.For a given amount of solute,smaller particles have greater surface area.With greater surface area,there can be more contact between particles of solute and solvent.

ex.If you piet granulated sugar in a glass of iced tea, it will dissolve mire quickly than the same amount of sugar in a cube.

Generalization:

The rate of dissolving is influenced by several factors,inluding stirring,temparature of solvent and size of particles.

The rate of dissolving a solute in a solvent is faster when the solute and solvent are stirred,the solvent is warmer,or the solute consist of smaller particles with more surface area.

Lesson 6:

Suspensions they are non-uniform,seperates into layers.Light paticles float and heavy particles sink,composed of insoluble particles.

Suspensions is a Heterogeneous mixture,which has particles do not completely dissolve and down at the bottom,suspensions are cloudy times.

Compositions and Inhaled Air:

Nitrogen-78%

Oxygen-21%

Other gasses -1%

Argon-1%

Carbon dioxide-0.04%

Density is a measure of the mass per unit volume of a substance.Vinegar has an density of 1.006 g/ml (glm3).Objects will float in liquid if their density is less than 1g/ml.Objects will sink in liquid if their in density is greater than 1g/ml.The oil is less dense than the vinegar.This is beacause the molecules of oil are larger than the molecules of vinegar,so oil particles take up more space per unit area.Its result,the oil will rise to the top of the water.

Lesson 7:

A colloid is a heterogeneous mixture which the dispersed particles are intermediate in size between those of a solution and a suspensions.They appear cloudy or milky.The particles are spread evenly throughout the dispensions medium,which can be solid,liquid or gas.

Colloids can be classyfied according to use/Function:

-Food items-Butter,Whipped

Beauty products-Hair wax,Facial moisturizer

Health and Medicine-antibiotic,ointment,cough syrup

Kitchen/Home item-Paint,ink

Colloids is a mixture of two or more substance.It is a special types of mixtures where tiny particles of one substance are scattered through in another substance.

Example of colloids:

1.Emulsion-mayonaise,milk,brewed coffee

2.Sol-ink,paint,blood,mud

3.Foam-whipped cream,styrofoam,marshmallow

4.Solid Aerosol-smoke,smog,dust,volcanic ash

5.Liquid Aerosol-perfume,mist,fog,hairspray

Importance and use colloids:

1.Colloids are use in diallysis

2.Colloids are used in pottery

3.Colloids are used in the artificial fiber industry

4.Colloids are use in the pharmaceutial industry

5.Colloids are used as liquid consituentof human blood

6.Colloids are used as deodorizes

7.Colloids are used in preparing food

8.Colloids are used as absorbent

9.Colloids are used as Aerosol Propellant.

Lesson 8:

Solutions are homogeneous mixture.

They have very small particles

Solutions are trasnparent are exposed to light

Solutions takes the properties of solvent solution

Colloids are heterogeneous mixture

They have intermediate particles (1-1000 nm)

Colloids give Tyndall effect (Scattering of light)

Colloids are in fact a type of suspensions

Suspensions are heterogeneous mixtures

They have large sizes particles (more than-1000 nm)

Light cannot pass through suspensions

Suspensions have intermediate properties of solute and solvent.

Lesson 9:

The advantages of hand picking:

* It is a very simple and easy method of seperation.

* It takes very little time when performed a small quantity.

* This method does not require any particular machinery.

The disadvantages of hand picking:

√ It is not feasible for large quantity of substances.

√It is a labor-intensive manual technique that could time.

√Imporities with a size smaller than the solid particles cannot be separated using this procedure.

The hand picking method:

•Hand picking is a separation technique used to remove the unwanted impurties from the mixture by hand.

•It involves simply picking out shbstances by hand and seperating them form others.

•Hanpicking method can be used when items differ on the basis of color,shape and weight.

Lesson 10:

Winnowing is the method in which heavier components of mixture are seperated from the lighter substances with the help of the wind.This method is used for seperating grains from husk after the process of threshing.

examples of mixture where the process of winnowing is used.

1.Rice grains and husk(chaff)

2.corn seeds and husk,dusk

3.sand and pebbles

Lesson 11:

Seperating Mixture through Decantation:

Decantation is technique used in seperating a less dense substance from a dense one.In the process of decantatio,th mixture is left undistributed.When the components are seperated,the less dense substance can be removed by slowly pouring out the less dense substance.The oil in the water could be remove using the decantation technique.

Examples of mixtures true decantation:

1.gassoline and water

2.singang with floating fats.

3.mud and water.