L7: Lipids' properties

P.7

Lipids Properties:

Lipids are a heterogeneous group of compounds synthesized by organisms that are present in all biological tissues. These compounds are characterized as natural substances that do not mix with water but dissolve in organic solvents. There are several classes of lipids including: fatty acids, waxes,triacylglycerols,phospholipids,terpens and steroids.
Like carbohydrate C,H and O are the principal elements of lipids although oxygen content is much reduced.
Lipids are made in general of long chains of hydrocarbons with relatively little oxygen. As a result of this, they tend to be non-polar, meaning that they do not dissolve in polar solvents such as water.
In this experiment we are going to test the solubility of different oils and how to identify lipids from a sample.


Objectives:

1- Test the solubility of lipids .
2- Identify lipids in liquids compouns
3- Understand what are an emulsion and the effect of detergents

Material:

Test tube rack
250 ml beaker
Water  90g
6 test tube
Cellullose paper
Dropper
Scissors
Glass road
Olive oli
Soap
Milk with differents fat content full-cream, semiskimmed and skimmed milk
Petroleum ether
Ethanol
Sudan III
Gogles
Google

Procedure:

Solubility of some lipids:

1- Clean and dry three test tubes.Label as W (Water) ethanol (E) and PE (ether)
2 Add 3 drops of oleic acid to small test tubes
3Add 1ml of  water in the first test tube(W)
4 Add 1ml of ethanol in the secone test tube(E)
5 Add1ml of petroleum ether in the third test tube (PE)
6 Shake carefully each test tube and record solubility and observations in your worksherret

Lipids identification

Transluced mark:

7 Cut  two pieces(10x10) of cellulose paper.
8 Put 1 drop of water in the first squared piece.You will see a translucent spot.Wit for a while and observere what happening.
9 Put 1 drop of olive oil in the second squared piece of cellulose paper. Your will see a translucent spot Wait for a while and observe what is happening.Has the spot disapperred?Why ?                           

  




Sudan III : Be careful Sudan red can stain clohes:


SudanIII is a red fat-soluble dyethat is utilized in the identification of the presence oflipids, triglycerids and lipopr4oteins in liquids
10 Take the W test tube of thefirst experiment and add 2 drop of SudanIII
11 Prepare four test tube: 3 with milk with differend fay content fat content (M1,M2,M3) and soda (S) .Add two drops of SudanIII and observe the results.

Permanents emulsion:

We put 100 mL of water in a 250 mL beaker. We have put 2mL oil and we have mixed. When we saw what was happening, we have put a few drops of soap and have seen the change.

Observations and results:

1. Solubility of some lipids
Oil and water didn't mix, oil formed micelles when it is mixed amb ethanol. And in the third test tube, ether (organic compound) dissolved oil. 

2.Transluced mark

When we added a drop of H2O on the cellullose paper it evaporated and leaves no mark. However,  the oil left a translucent mark and stayed on the paper.

3. SudanIII

Sudan III is a fat-soluble ink and dye black the oil sampl. Unfortunately, Sudan III didn't work, perhaps because it was very diluted. 

4.Permanent emulsion

When water an oil are mixed, and stir with a sitrring rod, they didn't mix. A monolayer of oil and water formed in the beaker. But when we added soap and we stir again, oil formed little micelles that didn't unite and a permanent emulsion was formed.

Questions :

1-From your observation, which compounds can dissolve lipids?
      1- First test tube :water and oil ,don't mixt 
      2-Firts test tube :oil and ethanol - oil formed micelles
      3- Firs tes tube:oil and ether - ether ( organic dissolvent) can disolvent

2-Do the oil and water mix? what can you conclude about the polarity of the oil if you know that water is polar?

 No, becose water is polar and the oil is non polar 

3- Why is liquid the olive oil at room temperature? and why not the lard?

   Oil has a lower point function as the carbon chain is shorter and lamantega to come from      animal fat carbon chain is longer and more difficult to breaK.

4- Why does a lipid leave a translucent spot on paper?

     Because fat oil does not evaporate the water instead if

5-  Which type of milk contains more lipids? why?

    Whole milk because it has more fat because the skimmed or semi skimmed Redi been    industrially fat content in milk

6-  Did the oil and water mix when you added the soap?

    Makes the water slide so fat formed by the oil disappear

7-  What did the soap do to the fat?

       The soap dissolves in oil miseles

8- Can you think about process and locations were compounds like the soap would be    important to an animal?

  Bile acids are part of the sterols are importan

P6: Fehiling's testst

P.6 


Fehiling's testst:  Reducing sugars 


Introduction:

Fehling's solution is a chemical test used to differentiate between reducing and non-reducing sugars.This test is based on the reaction of a functional group of sugar molecules with Fehling's reagent.
Fehling's reagent has two separate solutions:Fehling's A and Fehling's B

Fehling's A : Is a blue aqueous solution of copper (2) sulphate.
Fehling's B : Clear  and colourless solution of potassium sodium tartrate and sodium hydroxide.

When both mixtures are mixed a deep blue colour solution can be seen.When a sugar has reducing ability, the mixture turns from deep blue colour to green colour suspension with a red precipitate

Some sugars are capable of reducing copper 2 ions to cooper 1 ions .This  reducing ability is useful in classifying sugars .When the sugars to be tested is added to the Fehling's solution and the mixture is heated, some sugars can be oxidized( to lose electrons) and the Fehling's mixture can obtain this electrons ( reduced).

Objectives :

1 - Identify reducing sugars .
2 -Comprehend redox reactions.
3 - Understand the relation between structure and reducing abiliy of some sugars.



Materials:

Test tube rack
10ml Pipet
Distilled water
5 test tubes
5 spatula

Lactose
Maltose
Glucose
Sucrose
Starch
Fehling's A and B solutions
HCL

Procedure:

In this experiment you will first determine with sugars give a positive test with Fehling's reagent and then by , testing the reactions of some organic molecules containing only a single functional group, you should be able to deduce which funcional group of sugar is reacting with Fehling's reagents.

1 -Take 5 test tubes and label:G,M,S,ST
2 -Put 2ml of distilled water inside each tube
3 -With different spatulas put a small amount of each sugar.Dissolve the sugar.
4 -Add 2ml of Fehling's A solution and the Fehling's B
5 -Place each test-tube in a boiling water bath (250ml beaker on hotplate stirrer)
6 -Observe what is happening

Starch Hydrolysis:

Hydrolysis is the reaction of a compound with water.As you know,starch is a polymer, consisting of many units of alfa-D-glucose covalenty linked togerther
 7- Place 2ml of 1% starch in a test tube and  add 0.5 ml of3M HCL.Mix and place this mixture in a boiling water bath for 10minutes
 8- After 10 minutes , remove the tubew from the water bath and let it cool.Neutralize this solution      with 1M NaOH and mix well
 9 -Transfer 8-10 drops of this solution to a small test tube .
10 -Add 1ml of Fehling's B
11-Heat for a few minutes in a boiling water bath
12-Record you observations.Compare the results of this test with your results for unhydrolzed starch    in the step 1 of this expereriment.
13- You can test the absence of starch with iodine solution too!

Results:

G ,M , lactouse: have reacted with Fehling reagent.The solution turs from ,blue to starch and sucre didn't reduce.
Fehling reagent.They are not reducing sugars.

Questions :

1 -From your observations and the structures of the sugars given above ,indicate which functional group in the sugars molecules reacts with Fehling's reagent
-Totes han reaccionat menys la sacarosa perque el seu enllac es fa entre el-OH del carboni enumeric del primer monosacarid i el -OH del segon monosacarid, acausa d'aixo es l'unic disacarid que no te poder reductor sobre el reactiu de Fehling
2 -Compare the results you obtained for the fehling's test of starch and Fehling test of hydrolyzed starch.Explain your resuls.
-El mido hidrolitzat era de color vermell i el que no estaba hidrolitzat era de un color mes fosc que hauria de haver sigut lila.
3 - Would you have obtained a Fehling's positive test if you had hydrolyzed the sucrose (as you have done with starch)? Why?
- Si  s'hidrolitza es te una barreja de D-Glucosa i D-Fructosa ,i sobte levogira una substancia que desvia el pla de la llum polaritzada cap a l'esquerra.
4 -What does "reducing sugars" term mean?
-cuantsevol sucre que tingui un gup aldehi , o que pugui formarne un ,i que pot oxidar-se i passar electrons a un altre element o compost

P5: Saccharides properties

P5 .Saccharides properties



    INTRODUCTION

Saccharides are organic molecules consisting of C,H and O atoms. Usually the empirical formula is Cn H2n On  Are divided into three groups:

Monosaccharides: Formed by a linear carbon chain, are the building blocks of oligo and polyacchareides.They have a one funcional group:cetone (C=O) or aldehyde (COH). Pentoses and hexoses can switch from acyciclic to cyclic forms called furanoses and pyranoses. Ex Glucoses,galactoses or fructoses.
Oligosaccharides: small polymer containing between 2 and 10 monosacharides. Ex .Lactose,sucrose or maltose.
Polyasacchairides: Big polymers with more than 10 monosacchair .Ex Starch glycogen,cellulose and chiti
These molecules perform numerous roles in living organisms like storage if energy (starch,glycogen ),structural components cellulose, ribose,chitin or desoxiribose)

Saccaharides yield 4,2 Kcal /gr and are abundant in fruits,sweets,honey,tubers,rice,pastas and cereals. They are a common source of energy in living organisms


Objectives:

1 -Identify differents sugars from its properties
2 -Differentiate mono and disaccharides.
3 -Understand the relation between structure and some properties.

Material :

Test tube rack
10ml pipet
Dostilled water
5 test tubes
1dropper
5 Spatula
Lactose
Maltose
Glucose
Sucrose
Starch
Lugol's iodine
Distilled water

Procedure:

Complete the properties ' table that you have below from the 5saccharides you have at the lab:

	Glucose(G)	Maltose(M)	Sucrose(SU)	Lactose (L)	Starch(S)
Flavour sweet/ no sweet	NO SWEET	SWEET	VERY SWETT	NO SWEET	NO SWEET
Crystalline form	YES	NO	YES	NO	NO
Colour (White/Cream)	WHITE	WHITE	WHITE	WHITE	WHITE
Solubility soluble/insoluble)	YES	YES	YES	YES	NO
Lugol’s iodine +/-	-	-	-	-	+

1 -In the first part of the experiment we are going to test some physical properties of the saccharides you have in the lab : flavour , cryatal structure and colour .How?

   a) Flavour:Put a small amount of each saccharide in your hand and taste it!Is it sweet or not sweet?
   b) Crystals: Observe a small amount of each saccharide on a clok glass under magnification.
   c )Colour: white ,transparend or creamy

 To test solubility:

2 Clear and dry 5 test tubes and label them "G,M,L,SU,S"
3 Put 5ml of water in each test tube
4 With the aid of a spatula, put a small amount of each saccharide inside the labelled test tube and test if they are soluble or insoluble .
4 Observer if each saccharide forms a mixture called dissolution or a colloidad suspencio

Lugol's iodine Test:

6 Finally,add 2 drop of Lugol's iodine to each test tube and test if the reaction is positive or negative.Lugol's ia a solution of elementari iodine(|) and potassium iodine (KI) in water that is use to test a saccharide.The reaction is positive when iodine reacts by turning from yellow to a purple, dark-blue/ black colour.


QUESTIONS:

1-Write the empirical formulaof each saccharides  thaty you have use.Show structures of the five saccharides.Classiify eeach one in one group: mono,oligo or polysaccharide.
Disacarid ,Lactose( C12H 22O 11H 2O )( C6H10O5) Polisacare and glicos-n. Gluctosa,Fructosa C12H22O11 Disugre( C6H12O11) Maltosa disacarid (C12H22O11)

2- Which of the monosaccharides are aldoses and which are ketoses?
Polysaccharides were those who were not sweet unless it was a lactose monosaccharide
3- Which bond links monosaccharides?
Aldehyde link
4-Which saccharide/s is / are sweet? Is this property related to the structure of thr molecule?
Maltose binding aldei i ketone link sucrose

5- Which saccharides/ s is/ are insoluble?Is property rerlated to the structure of the molecule?
Are insoluble G, M, L SUB link aldosa

6-Whitch saccharide has reacted with Lugol's iodine solution?
Reacted Starch
7-Which kind of foods contain starch ?
Flour
8-Calculate the energy from the nutrion facts label from a cereal:
        a) Calculate the energy that coments from the saccharides.
                96,6
        b) Which% of the total energy come from the saccharides?
               0,4%

L4: PH

    pH

   INTRODUCTION:

The pH is a measure of the acidity or basicity of a solution.Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline . Pure water (distilled water) has a pH close to 7 neutral.
The pH is defined as the following equation:
               

                                                           pH=-log (H+)


For mesuring the pH of a solution at the lab we have different pH indicators:
Universal indicator paper : It't an absorbent paper that has been impregnate with universal indicator. This method consist as a continuous colour change from about pH 2 to pH10.
-pH-meter: is an electronic device used for measuring the exact pH of a solution.It consists of glass electrode connected to an electronic meter that measures and displays de pH reading.

Objective:


1-Measure differents pH values of organic and inorganic solutions.
2- Prove different methods of mesuring pH






 Material:  

-Beaker
-Watch glass
-PH indicator strips
-knife
-1 lemon
-1 tomato
-wine
-milk
-Dissolution of sodium hydroxide
-Vinegar (acetic acid)
-Hydrochloric acid 10%
-ammonia
-bleach
-distilled water
-dissolution soapy




Procedure :

To measure the pH of different solutions  we arebgoing to put the different solutions small beakers of 250ml

Squeeze the lemon and tomato in two clock glasses. Take a piece of indicator paper and place one end of it into the solution . Leave for at least 20 seconts.Remove the indicator paper and compare its colour with  the appropriate colour chart. Repeat points one to two with as many others solutions as you are provided with.Record your results in a resuls table in your worksheet.
The consentrer of pH

Prepare a test tub rack with five test tubes cleaned with distiller water.Mark the tube with the labels:A, A1,A2,A3 and B
Add 10ml of lemon juice to tubes A and B
Take the A tube and put 5ml of ist lemon juice to test tube A1
Tke the A1 tube and put 2,5 ml of its lemon juice to tube A2
Take the A2 tube and put 1,2ml of its lemon juice to tubeA3
Add distilled water to each test tube until in has the same volume as test tube B 10ml
Calculate the concentration of each test tube with the formula you have below:

Find the pH of each of the test tube and record the information in the table:

TEST	VOLUME OF	TOTAL	CONCENTRATION	pH
B	10	10ml	100%	2,95
A1	5	10ml	25%	3
A2	2,5	10ml	12,5%	3,05
A3
A	10	10ml	50%	3

Observaccions:

Enter peaquimetres to see solutions and the degree of accidesa they had, then the lemon we had another experiment fen differents consentrecions acid and distilled water with lemon .But the result was different between the degree of co accidesa gave us.





Questions 

Which of the solutions gave an acid pH? HCL ,Vinager,Tomato,Coffe,Wine,Milk
Which of the solutions was alkaline? Soap,NAOH,Bleach
Which of the solutions were neutral?Did you expect these results? Explain.
Destiled  wotter , because we noticed a small amount of salt and.
How does a pH of 3 different from pH of 4 in terms of H concentrations?  Que el tres te  deu vegades mes protons que la quatre
In the second part of the experiments ,have you have compared the pH of the same product (lemon juice) in different concentrations . In this case explain.
concentration varies lemon juice distilled water possavem that was more acidic or neutral

a-Which is the dependent variable? is pH
b-Which is the independent variable? Dissolution is that we put distilled water
c-Which is the problem that we want to solve?distilled water so that the lemon juice makes it more neutral
d- Which is the control of the experiment?
e-Write the results and conclusions of your experiment:
Els resultats de l'experiment no son correctes el peaquimetre es va descalibrar

Which pH do you think that gastric juice might have?Why?Do you thinks in intestinal pH has the same pH?Why? Tenim en el nostre estomag acid gastric que te un pH de 12-13 tenim acid cloridric que ens desfa els aliments i tenim una pared a lestomag perque aquets sucs gatrics no surtin ja que podrien provocar molt de dolor.

Which pH do you think that blood minght have?Why? Es de 7,2 intentaser lo mes neutre possible perque no pogui tornar la sang que porta l'aigua i altres conponens de vital inportancia en acids o basics
What is acid rain? Whichare the consequencies in the ecosystems and how is its formation pattern ?In rain Barcelona acid or alkaline ? Es tota la pluja que presenta un pH inferior al del normal, es perjudicia pel creixement de les plantes i contribueix al deteriorament del medi. Es produeix per que en la humitat de l'aire  hi ha sofre nitrogen que produeixen les fabriques.

L3: Osmosis

Introduction:

Osmosis is the spontaneous movement of solvent molecules through a semipermeable membrane into a region of higher solute concentration (hypertonic), in the direction that tends to equalize the solute concentrations on the two sides. Osmosis is a vital process in biological systems, as biological membranes are semipermeable. Water molecules travel through the plasma membrane in order to equilibrate the intra and extra cellular concentrations.When a cell is submerged in water, the water molecules pass through the cell membrane from an area of low solute concentration to high solute concentration.When the extracellular concentration is hypertonic, water moves out of the cell and the cell becomes flaccid:PLASMOLYSIS.When the extracellular concentration is hypotonic, water moves inside the cell and it becomes TURGID.

Objectives:

1. Know about the osmosis phenomena.
2. Understand the process of osmosis in plasmatic membranes.


Materials:

• Egg
• Potato
• Salt
• Distilled water
• Acetic acid (or vinegar)
• Spatula
• 600 mL Beaker
• 3 Clock glass
• Pen
• Spoon
• Knife

Procedure:

Egg: this experiment will be divided in two days.
Under the hard outer shell of a chicken egg is a semipermeable membrane that allows air and moisture to pass
through. Because water molecules can move into and out of the egg but larger molecules cannot, the
semipermeable egg membrane allows for an exploration of concepts of diffusion and osmosis.

1st Day:
Before the egg osmosis experiment can begin, the egg’s hard outer shell must be removed. Let’s start with
this:
1. Take a 600mL beaker and put inside the egg.
2. Cover the egg with vinegar and make note of what’s happening.
Once the egg’s shell is removed and the egg is rinsed dry and clean, measure and weigh the egg. Record
the dimensions of each egg in a table.
3. Clean the beaker and put the egg inside again.
4. Cover it with distilled water. Make note of the volume of solution inside the beaker.

2nd Day:
5. Left the egg one day in the distilled water. After about a day, carefully remove the egg using a spoon.
Rinse the egg with water and let it dry.
6. Measure again the dimensions and record its weight.
7. Make note of the solution volume in the beaker and notice if there has been any difference.
8. Observe the results and write your conclusions in your lab worksheet.

Potato:
1. Lay out the three watch glass.
2. Slice the potato in three parts lengthwise. Each slice must be of 1,5cm thick.
3. Place each slice onto a watch glass and make a hole in the middle of each slice. NOTE: the hole does not
have to cross the slice!
4. In the first slice hole, don’t put anything. The second fill it with salt and the third with distilled water.
5. Left this preparation 30 minutes and make note of what is happening.

Observation of the egg :

First he gave off carbon dioxide disappeared after the first layer of skin that was semiperneable and become whiter in color with a touch different
Obserbacio potato :

the potato that we did not even throw salt or distilled water was oxidized to which we possa salt water to loosen regulate hypertonic saline became so limp became more however was softer potato with distilled water swelled and stood among them is the process of Turgut was hypotonic
conclucio potato
If the potato strips salt will lose water and distilled water if litires cells sinflaran harder and tare
Conclucio egg:


Questions;

Egg experiment:

1. What is happening when the shells are soaking of acetic acid?Sestan disolen dejuta l'acid que les va desfem pero una de les petxines no es va desfer perquè era mes resistien i no libem tirar suficient acit clorhídric, les altres el van desfer i va quedar nomes la part inorgànica.

2. Write the results of de dimensions and weigh of the egg before and after immersing it in distilled
water. Write and draw a simple diagram of the water direction.

Potato experiment:

3. Explain the results of this experiment.La patata amb sal es va tornar mes tova perque sigualesin les consentracions de sal va haver de despendre aigua i l'altre va absorvir l'aigua destilada per igualar la solucions
4. Why have we left the first slice without any treatment (salt or distilled water)? Per que el resultat sigui en las mateixes condicions amb les mateixes patates el mateix   ambient utensilis i que poguem compra els resultats
5. Which are the dependent and independent variables?les dependents seria l'aigua destil·lada i la sal i la independent la patata sense modificar
General questions:
6. How can you explain (through osmosis) the ability of plant roots to draw water from the soil?
Per que es necessita regular la concentració de salts i les plantes absorbeixen aquestes salts del terra i la pluja per regular les dissolucions i que siguin isotòniques

7. What will it happen if a saltwater fish is placed in a freshwater (low concentration of salts)
aquarium? El peix esta acostumat a viure en unes condicions  que l'aigua dolça no te, la salinitat del cos d'aquest peix baixaria i es moriria

8. Look the image you have below and explain what is happening to the erythrocytes in each situation:
A la primera hi ha un increment de sal i els globuls vermells es quedarien sense aigua esta patim un proces hipertonic , la segona es regula perquè te una quantitat estable de aigua i de sals, la tercera te un augment d'aigua destil·lada que faria perdre sals per aixó si veguesim aigua destil·lada ens podrirem mori

bones

INTRODUCTION

even though bones are very lighy,they are also very strong .however how streong they are depends on how much of the mineral calcium carbonate they contain.
Eggs and bones contain calcium carbonate (CaCo3). When calcium carbonate and acetic acid combine a chermical reacion takes place and carbonate dioxide(Ca2) is released.We can see thi effect observing  some bubbles in de solution
bones are place in the glass with acetic acid ,this acid dissolve the calcium carbonate so that only collagen in left.
During foetal development strong fibbers of collagen protein form a matrix for bones.the matrix is shappen like bones but is very flexible.The matrix  solidifies by a process,called calcification.Duringthis process calcium phosphate or  hydroxyapatite is depositied in the fibbers of collagen and give the bonesstrength and rigidity.

Objectives: 

1-Identify mineral salts in organisms
2- Understand the funcion of inorganic biomolecules in skeletal structuresof organisms


Material:

Wash bottle
Beaker 100ml
Beaker 200ml
Watch glass
Forceps
vinegar
lab coat
acetic acid
Bones 7g , 2,1g  4,8g


Procedure:

 Chiken or lambs bones:

1: Carefully clean and cut ad much of the meat away from the chiken thin bone as possible
2 Examine the flexibility of the bones by trying to brnd it with your fingers
3 Take a beaker and make and acid acetic solution or add vinegar
4 Take the chicken or lamb bones and drop them in the acid acetic solution that you have made
5 Leave it 24-48 hours and see what happens to the bone.Put a clock glass at the top of the beaker to      protect de solution
6 Remove the bones from the vinegar with a tong and soak them with water.
7 Write the results in your lab worksheet.


Observacio:

We see as acetic acid melted organic matter of bones and soft finished tornance demanera that could boblegar a normal bones can not be so easily boblagar

 Conclucions:

Acetic acid rid organic matter and releases the CO2 that are making inside many properties of bone loss

Questions:


Write the reaction that takes place when the acid acetic reacts with the calcium carbonate.ç
-CaCO3+Cl3OOH+CO2

2. What is happening when the shells are soaking of acetic acid? What are the bubbles that you can
see?Es la materia orgànica que es despren i les bombolles son CO2

3. What is happening to the bone after some days of soaking it in acetic acid? Why is the bone
flexible now? Per que a perdut totes les propietats que tenia una de elles el calci que li donava resistència

4. So, what is the function of the calcium carbonate in the skeletal structures?Dona rigidesa als ossos

5. Increases in carbon dioxide to the atmosphere from the burning fossil fuels and deforestation
threaten to change the chemistry of the seas. Evidence suggests that this increase in atmospheric
carbon dioxide is lowering the pH of the oceans in a process called ocean acidification. How can
acidification affects corals reefs?
Es degut a la falta de PH a l'aigua ja que l'acidesa es molt alta en alguns llocs

welcome sciencie lab

Hello my name is Laura . I study in Centre d'Estudis Prad