1. The equation for the reaction of bromine and methanoic acid is

a. Suggest a way of keeping the concentration of methanoic acid virtually constant

b. The result of an experiment in which the concentration of bromine was monitored through out a reaction are shown in the table

Time ( s )	(/mol dm-3
0	0.01
25	0.009
50	0.008
75	0.007
100	0.0065
180	0.0050
240	0.0045
360	0.0030
420	0.0025
480	0.0020

Plot a graph of againts time show that this reaction is first order by working out three values for half life.

2. The half life of radioactive iodine 131 is 8.0 days what fraction of the initial amount of iodine 131 should be present in a patient after 24 days if none were to be eliminated through natural body process.

3. Explain why no external indicator is needed when titrating solution containing ethamidioated ions with potassium magnate (VII).

4. Calculated the volume of 0.02 mol dm^-3 potassium magnate (VII) solution need to completely oxidize 25.0cm³ if:

a. 0.01 moldm^-3 iron (II) sulphate solution

b. 0.2 moldm^-3 hydrogen peroxide solution

c. 0.1 moldm^-3 ethamidioate solution.

5. A 1,340 gr sample of iron are dissolved in dilute sulphuric acid to produce a solution of iron (II) sulphate this was titrated with 0.02 moldm^-3 potassium magnate (VII) solution and it was found that 28.75 cm³ was required. Calculated the percentage of iron in the iron ore.

Answer

1. Known : v olume bleach 2 cm³

0.05 moldm^-3

2.

Nt = 16.375 gr

3. Because the potassium manganate (VII) has ability of self indicating. So, there’s no needed to its solution.

4.

a. Known :

Concentration of KMnO₄ = 0.02 mol dm^-3

Volume = 25 cm³ = 25 x 10^-3 dm³

Concentration of FeSO₄ = 0.01 mol dm^-3

Solution :

Amount of KMnO₄ = 0.02 mol dm^-3 x 25 x 10^-3 = 5 x 10^-4 mol

From redox equation :

MnO₄^-_(aq) + 8H⁺_(aq) + 5Fe²⁺_(aq) à 5Fe³⁺_(aq) + 4H₂O_(l) + Mn²⁺_(aq)

1 mol of MnO₄^- will react with 5 mol of Fe³⁺

So, the amount of Potassium manganate (VII) = 5 . 10^-4 mol x 5 = 25 . 10^-4 mol = 2.5 x 10^-3 mol

4B. Known :

Concentration of KMnO₄ = 0.02 mol dm^-3

Volume = 25 cm³ = 25 x 10^-3 dm³

Concentration of H₂O₂ = 0.2 mol dm^-3

Solution :

Amount of KMnO₄ = 0.02 mol dm^-3 x 25 x 10^-3 dm³ = 5 . 10^-4 mol

From redox equations :

MnO₄^-_(aq) + 8H⁺_(aq) + 5O^-_(aq) à Mn²⁺_(aq) + 5/2O_2(aq) + 4H₂O_(aq)

1 mol of MnO₄^- will reacts with 5/2 mol of O₂

So, the amount of Potassium Manganate (VII) = 5 . 10^-4 mol x 5/2 = 1.25 x 10^-3 mol

4C

Known :

Concentration of KMnO₄ = 0.02 mol dm^-3

Volume = 25 cm³ = 25 x 10^-3 dm³

Concentration of FeSO₄ = 0.01 mol dm^-3

Solution :

Amount of KMnO₄ = 0.02 mol dm^-3 x 25 x 10^-3 = 5 x 10^-4 mol

From redox equation :

MnO₄^-_(aq) + 8H⁺_(aq) + 5C₂H₄O₂^-_(aq) à Mn²⁺_(aq) + 5/2 C₂H₄O_{2 (aq)} + 4H₂O_(aq)

1 mol of MnO₄^- will react with 5 mol of Mn²⁺

So, the amount of Potassium manganate (VII) = 5 . 10^-4 mol x 5 = 25 . 10^-4 mol = 2.5 x 10^-3 mol

Question and answer about alkynes

1.what is the acetylene?

a. the material that used in hydrocarbon reaction

b the material that resulted by the alkynes reaction

c. the material that needed to do the reaction

d. the starting material for the preparation of many useful compound

e. the yield of the reactions

2. what is one of the product of methane process that heated to a very high temperature?

a. acetylene

b. propanes

c. hydrogen

d. ethane

e. water

3. what is the name of this structure:

CH3 C2H5

| |

CH2–C≡C–CH–CH–CH3

|

CH3

a. 5,6–dimetil 3– heptuna

b. 2,3–dimetil 4– heptuna

c. 5,6–dimetil 3– oktuna

d. 3,4–dimetil 4– oktuna

e. 6–etil 5–dimetil 3– heptuna

4. what is the function of addition of halides to the alkynes?

a. to fast the alkynes reaction

b. to make stronger the alkynes reaction

c. there is no impact if the alkynes we add by halides

d. to increase the velocity of the alkynes reaction

e. to opened the triple bond become double bond and then single bond

5. what is the final result of butyne if we adding by hydrogen chloride?

a. 2– chloro butene

b. 2,2– dichloro butene

c. 2– chloro butane

. d. 2,2– dichloro butyne

e. 2,2– dichloro butane

6. what is the different between alkynes and alkanes based on their physical properties?

a. boiling point of more then alkanes

b. alkynes are more soluble in solvent of low polarity than alkanes

c. alkynes is ore slightly soluble in water than alkanes

d. the reation of alkynes is faster than alkanes

e. the density of alkynes is less than the alkanes

7. The compound named 2-butyne has

a. a chain of four carbon atoms with a triple bond between C2 and C3
b. a chain of four carbon atoms with a double bond between C1 and C2
c. a chain of four carbon atoms with a triple bond between C1 and C2
d. a chain of four carbon atoms with a double bond between C2 and C3

e. a chain of four carbon atoms with a single bond between C2 and C3

8. The addition of HCl to 4-methyl-2-pentyne follows Markovnikov's Rule. The product is

a. 2,2– dichloro – 4 methyl pentane

b. 2– dichloro – 4 methyl pentane

c. 2,2– dichloro butyne

d. 2,2– dichloro butane

e. . 2,2– dichloro butane

answer:

1. answer :D.

Reason: because acetylene is used as a starting material for preparation of many useful compound.

2. answer : A

Reason: because acetylene is one of product of ethane process that heated to a very high temperature.

3. answer : C

Reason : because the longest chain is 8 so it is oktuna and the branch is placed in number 5,6 atom C. and the triple bond is placed in the third of atom C

4. answer : E

Because if we add the alkynes with halide the triple bond become opened.

Ex: Br Br Br

| | | |

– C ≡ C – + Br2 → C = C + Br2 → – C – C –

| | | |

Br Br Br

5. answer: E

Reason : because based on the reaction :

CH3 – CH2 – C ≡ CH + HCl → CH3 – CH2 – C = CH2

|

Cl

Cl

|

CH3 – CH2 – C = CH2 + HCl → CH3 – CH2 – C = CH2

| |

Cl Cl

6. answer: C

Reason : because alkynes are only very slightly soluble in water although they are somewhat more soluble than alkanes.

7. answer : A

Reason : because based on the structure:

C – C ≡ C – C

8. answer : A

Reason : based on the reaction:

Cl

|

CH3 – C ≡ C – CH – CH3 + HCl → CH3 – C =C – CH – CH3

| |

CH3 CH3

Cl Cl

| |

CH3 – C =C – CH – CH3 + HCl → CH3 – C – CH – CH – CH3

| |

CH3 Cl

2,2– dichloro – 4 methyl pentane

ASSIGNMENT OF NUTRITIONAL CHEMISTRY

MEMBER OF GROUP :

FITRI MAULIDA SARAGI (409332018)

IKA IRAYANI (409332008)

LIA ISTI INDRIYANI(409332023)

MASITHO PURNAMA SARI(409332025)

RAHMI WARDHA LUBIS(409332028)

RAJA IHOT SIAHAAN (409332029)

SITI RAHMAH(409332030)

Question :

1. Which vitamin act as hormone in active form?

2. Which vitamin has been shown to be terratogenic when use in excess ?

3. What vitamin provide protection against free radical within membrane cells?

4. Name a vitamin that help to destroy free radicals within the cytosol ?

5. The food of nutrition board of the national academy of science recognize with substance as the water soluble vitamin ?

6. Name at least two vitamins that tend to be destroyed by poolong cooking ?

7. Which vitamin prevent beri – beri?

8. Which vitamin when taken during all before pregnancy protection against neuraltube defense ?

9. What criteria makes the distinction between mineral and trace elements ?

10. Name and give the chemical forms of the six mineral !

11. Make a table of the ten trace element and at least one particular function of each !

12. What kind be the bodies respon to an iodine deficient diet ?

Solution :

1. The vitamin that act as hormone is vitamin D. Vitamin D is carried in the bloodstream to the liver, where it is converted into the prohormone calcidiol. Circulating calcidiol converted into calcitriol. When synthesized in the kidneys, calcitriol circulates as a hormone, regulating among other things.

2. The vitamin that can cause teratogenic when use in excess is vitamin A. Some and maybe all forms of vitamin A when taken in excess are also know to be teratogenic (they cause birth defects). So it is not recommended vitamin supplements with extra vitamin A be taken by pregnant woman.

3. Vitamin that provide protection against free radicals within membrane cell is vitamin E. Because β carotene and vitamin E are both fat soluble. They are actually able to enter the lipid rich environment of the membrane to protect the membrane.

4. Vitamin C, because vitamin C is also a destroyer of free radicals. Because it is water –soluble, it is able to do this work within a cell’s cytosol.

5. The water-soluble vitamins are vitamin C, cholin, thiamine riboflavin, nicotinamide, folate, vitamin B₆, vitamin B₁₂, pentothenic acid, and biotin. These are the water-soluble vitamins recognized by the food and nutritionboard.

6.

a. Niacin, meaning both nicotinic acid and nicotinamide, is essential . For nearly, all biological oxidations. Prolonged cooking destroys niacid.

b. Vitamin C is present in citrus fruits, potatoes, leafy vegetables, and tomatoes. It is destroy by extended cooking, heating over stream tables, or prolonged exposure to air or to ions or copper.

7. Thiamine (B₁) is needed for the break down of carbohydrates. It is defiency disease is ‘beri beri’, a disorder of the nervous system.

8. Folate is the name used by the food and nutrition board for folic acid and related compounds its use duringthe first four weeks of pregnancy was particularly important. A large controlled study in bungary showed that vitamin-minerals supplement, including folic acid, resulted in 50 % fewer congenifal. Malformations of all kinds, when taken prior to pregnancy.

9. The distinction between a mineral and trace element is matter of quantity.

a) Minerals are needed at levels at 100 mg/day or more, example : calcium (Ca²⁺), phosphorus, magnesium (Mg²⁺) and sodium (Na⁺)

b) The trace elements are needed at levels at 20 mg/day or less, example : fluorine, iodine, chromium, iron.

10. The minerals are :

Calcium (Ca²⁺)

Phosphorus (phosphate ion, P)

Magnesium (Mg²⁺)

Sodium (Na⁺)

Potassium (K⁺)

Chlorine (Cl^-)

11.

NO	TRACE ELEMENT	FUNCTION
1	Fluorine (as fluoride ion)	Essentials to the growth and development sound teeth
2	Iodine (as iodide ion)	Essentials in the synthesis of the certain hormones made by the thyroid gland
3	Chromium (Cr3+)	Is required for the work of insulin and normal glucose metabolism
4	Manganese (Mn2+)	Is required for normal nerve function, for the development of sound bones, and reproduction
5	Iron (Fe2+)	Is essentials cofactor for heme certain cytochromes, and the iron sulfur proteins
6	Cobalt (Co2+)	Without it there can be anemia and growth retardation
7	Copper (Cu2+)	It deficient in copper, the individual synthesizes lower-strength collagen and elastin and will tent to suffer anemia, skeletal defects, and degeneration of the myelin sheaths of nerve cells
8	Zinc (Zn2+)	Is required for the activities of several enzymes
9	Selenium	It is needed for thyroid hormone action
10	Molybdenum	Is required for the metabolism of nucleic acids as well as in some enzymes that catalyze oxidations

12. Iodine (as iodide ion) is essentials in the synthesis of certain hormones made by the thyroid gland blets deficient in iodide, ion cause an enlargement of the thyroid gland known as a goiter.

Pelatihan IT/ICT UNIMED keren euuuyyy....

Mengikuti program IT/ICT UNIMED tanggal 27 Juli 2011 sangat menyenangkan

STRES MENDERA REMAJA

Stres adalah gejala tekanan mental yang menyerang organisme yang ditandai dengan adanya sakit kepala yang abnormal. Banyak remaja sekarang yang menderita stres. Tekanan pelajaran ataupun dari kegiatan yang menyita perhatian mereka dapat menjadikan mereka stres. Tidak di pungkiri lagi bahwa gejala ini menjadi momok yang sering melanda remaja sekarang.