EXPLANATION TEXT, QUESTION, AND ANSWER ( TEKS EKSPLANASI, PERTANYAAN, DAN JAWABAN)

How Is A Kite Flying?

A kite is an object which is made from a light material stretched over a frame. Due to its light material a kite will lift off the ground and fly when it is tilted into the wind.

A kite is uses wind to make it fly because it is heavier than air. When wind travels over the surface of the kite, it is split into two streams of air. One stream of the air goes over the kite while the second stream goes under the kite. 

The upper stream above the kite. The lower stream hits the kite at a shallow angle and creates an area of high pressure. 

The high pressure area has a pushing effect while the low pressure area has a pulling effect. The combination of push and pull can creates enough force to lift the kite into the air. 

Kites have been known for thousand of years. They are used for military or scientific purposes. Todays kites are much used for leisure and competition.

1. What media which use by kite to fly?

a.     Air

b.    Water

c.     Ground

d.    Light

e.     Wind

2. How many stream of air if we want the kite flying?

a.     Two

b.    One

c.     Four

d.    Three

e.     There is no stream

3. The first Word of  “ it” at the first line of paraghraph two is refer to

a.     Wind

b.    Air

c.     Kite

d.    Frame

e.     Fly

4. What is the function of the upper stream?

a.     hits the kite at a shallow angle

b.    creates an area of high pressure

c.     creates an area of middle pressure

d.    creates an area of low pressure

e.     give space for kite to fly

5.  Bassed on the text, what is the function of kite at past?

a.     Used for competition

b.    Used for military

c.     Used for sent message

d.    Used for sent money

e.     Used for keep home for annoying evil

How Cell Phone Work

A cell phone is a great gadget in this modern world. What is a cell phone? A cell phone is actually a radio in certain way. Like a radio, by a cell phone we can communicate to other people in real time. Million people use cell phone for their communication. Even nowadays, people use cell phones to communicate in voice, written and data.

Alexander Graham Bell is the person who make great change in the way people communicate to each other. He invented a telephone in 1876. While wireless radio was formally known in 1894 presented by Guglielmo Marconi. By these two technologies, then a cell phone was born. However do you know how actually cell phones work?

This short explanation on how a cell phone work is really wonderful. A cell phone or in long term "cellular telephone' works by transmitting signals of radio to towers of cellular. The towers are networked to a central switching station. The connection usually uses wire, fiber optic-cables, or microwave.

Then the central switching station which handles calls in certain given area is directed connected to the wire-based telephone system. Cellulars are pick up by the towers and relayed to another cellular telephone user or the user of wire-based telephone network.

the towers vary in the capacity and capability to receive signals. Some can receive the signal from short distance and the others can receive more distance. However, there are usually more than one tower in certain given area so that the system can handle the increasing telephone traffic.

1.       Who is the founder of cell phone

a.       Franklin

b.      Graham Bell

c.       George rude

d.      Marconi

e.      Glorious frederick

2.       Who is guglielmo Marconi?

a.       The founder of cell phone

b.      The founder of switching station

c.       The founder of telephone

d.      The founder of telephone traffic

e.      The founder of wireless radio

3.       What station which handles calls?

a.       The central switching station

b.      Traffic station

c.       Distributary station

d.      Local station

e.      Towers station

4.       What is the main idea of the second paragraph?

a.       Alexander Graham Bell

b.      wireless radio

c.       Guglielmo Marconi

d.      The process of the born of cell phone

e.      How cell phone work from station

5.       Based on the text, how the cell phone work

a.       By transmitting signals of radio to towers of cellular

b.      By traffic

c.       By receive the password

d.      By find the code

e.      By internet

REPORT TEXT , QUESTION, AND ANSWER ( TEKS REPORT, PERTANYAAN, DAN JAWABAN)

REPORT TEXT

Durian

Durian is the name of tropical vegetation which comes from southeast asia. It is also the name of fruit. This name is taken from its skin characteristics which is similar with “duri” or thorn. Its famous name is King of Fruit. Durian is a controversial fruit because many people like it but many of them hate its smell.

Because the strong smell of it, and it tends to smell rotten, some transportation companies forbid people bring durian, for example in the plane, public transportation or into the hotel. However, many people still like durian. Durian is quite expensive.

Durian has various kinds. There are 20 species of durian in Indonesia. Nine of them can be eaten. Durian fruit is eaten when it is in the fresh condition. In general this fruit is sweet and very nutritious because it consists of carbohydrate, fat, protein, and mineral.

In the harvest season of durian, this fruit is everywhere, especially in its production centre region. Traditionally, the flesh of the fruit can be cooked with sugar and it becomes “lempok or dodol” or it can be fermented to be tempoyak. The taste of tempoyak is sour and it is usually eaten with sambal or to be additional ingredient to cook fish.

Sometimes, durian can be mixed with other traditional cake ingredients like gelamai or jenang. It is also mixed in the desert with glutinous rice. In this modern era, the taste of durian is also added in candy, ice cream, milk, and other kind of fresh drink.

The seeds of durian can be eaten as snack after being boiled or roasted. The raw seed cannot be eaten because it is poisonous. It consists of cyclopropene, a poisonous material.

Some of durians are sometimes used as traditional medicine materials. Its root is used as fever medicine. The leaves can be mixed with Acorus calamus leaves and it is used to cure infection on nails. The skin of the fruit can used to cure skin diseases and constipation. Some of Javanese societies use the skin of durian to shoe mosquito and put it on the corner of the room. The durian fruit is a good source of antioxidant vitamin-C. It can help the human body develop resistance against infectious disease.

Moreover, it contains minerals like manganese, copper, iron and magnesium which is utilized by the body for the antioxidant enzyme. Copper is needed in the production of red blood cells. Iron is needed for red blood cell formation. Fresh durian fruit is the source of potassium which is an important electrolyte inside cells and body fluids that control heart rate and blood pressure. Further, it also contains high levels of essential amino acid, tryptophan which metabolizes into serotonin and melatonin in human body.

Durian flesh is also exported in the form of canned durian. In Bangkok, durian paste is mixed with pumpkin. Malays keep the flesh in salt in order it can still be eaten with rice, even though it has been a year. They always their own way to enjoy durian.

1.    Beside consist of carbohydrate, durian also consist …..

a.    Fat

b.    Vitamin a

c.     Vitamin B12

d.    Fiber

e.    Glucose

2.    “…it becomes “lempok or dodol” …”

The word “it” refer to

a.     Durian’s tree

b.    Durian’s seed

c.    Durian’s flesh

d.    Durian’s root

e.    Durian’s leaf

3.    What will happen if we eat uncooked seed of durian

a.     We will be poisoned because the large of seed too big

b.    We will be poisoned because the taste is not delicious

c.     We will be poisoned because that’s just for animal

d.    We will be poisoned because It consists of cyclopropene

e.    We will be poisoned because it concists of isomerization

4.    What kind of mineral in durian which needed in the production of red blood cells?

a.     Iron

b.    copper

c.     manganese

d.    kalsium

e.    magnesium

5.    what is the main idea of the last paragraph

a.     durian flesh

b.    exported durian

c.     canned durian

d.    durian in Bangkok

e.    the ways to enjoy durian

Human body is actually a living machine and is like all other machines. This living machine needs fuel to supply it with energy. The fuel is provided by the food which we eat. However do we know how much we need to stay healthy?

The energy value of food is usually measured in calories. A calorie is the amount of heat which is required to raise the temperature of 1 kg of water by 1 degree C. The number of calories which people need per day varies. It depends on the activity which the people are involved in. For example; people will need more calories for standing than for sitting, people need more for running than for walking, etc.The energy which is provided by food is in the form of three kinds of chemical substances. They are carbohydrate, protein and fat. Carbohydrate provides 8.8 calories per gram (cal/gm) of energy, protein 4.0 cal/gm and fat 8.0 cal/gm. Each food contains different proportion of these substances.These three chemical substances are all important for body staying healthy.

1.     how can we fuel the energy of human body?

a.     We can do exercise

b.    We can eat

c.     We can read

d.    We can find it

e.    We can buy it

2.     How many calories which people need per day?

a.     8,8 calories

b.    8,0 calories

c.     4,0 calories

d.    Depend of the human

e.    Depend of the parents of human

3.     what is the best tittle for that text?

a.     Human

b.    Human energy

c.     Kind of energy

d.    Energy for human

e.    Human body energy

4.     which will need more calories, studying, sleeping, listening, or talking?

a.     Studying, talking

b.    Studying, listening

c.     Talking, listening

d.    Talking, sleeping

e.    Listening, sleeping

5.     How much fat provides calories for human body?

a.     8,8 cal/ g

b.    6,7 cal/ g

c.     8,0 cal/ g

d.    4,5 cal/ g

e.    1,0 cal/ g

contoh soal- soal kimia

1. Ada dua senyawa wujudnya gas, terbuat dari unsur X dan Y. Senyawa A mengandung 30,43% X dan 69,57% Y ; senyawa B mengandung 63,64% X dan 36,36% Y (% massa). Pada keadaan standar unsur X dan Y memiliki wujud gas namun Anda harus memperkirakan apakah gas–gas tersebut mono–atomik, di–atomik atau tri–atomik. Pada suhu tertentu 1 volum gas X dapat bereaksi dengan 2 volum gas Y membentuk 2 volum senyawa A. Jika 2 volume gas X bereaksi dengan 1 volum gas Y membentuk 2 volum senyawa B.

1.                 Hitung perbandingan massa atom X terhadap Y [6]

2.                 Perkirakan rumus sesungguhnya gas X dan Y [6]

3.                 Tuliskan persamaan reaksi yang mungkin untuk terbentuknya senyawa A dan B [8]

Pembahasan soal 1.
Perbandingan volum = perbandingan mol untuk keadaan standar. Volume X dapat dimaknai sebagai jumlah mol X dan volume Y dapat dimaknai jumlah mol Y.
Kita memanfaatkan informasi pada deretan kata pada soal itu. X dan Y adalah gas pada keadaan standar kemungkinannya adalah gas H₂, He, N₂, O₂, O₃, F₂, Cl₂. Di antara gas–gas tersebut yang mungkin membentuk senyawa XY₂ dan X₂Y hanyalah gas N₂ dan O₂ maka gas yang lain dapat diabaikan.

Jadi XY₂ itu adalah NO₂ dan X₂Y itu adalah N₂O
Kesimpulannya X adalah gas N₂ dan Y adalah gas O₂

Reaksi: X + 2 Y → 2A sehingga persamaan reaksi yang mungkin adalah N₂ + 2O₂ ⟶ 2NO₂
Reaksi: 2X + Y →  2B sehingga persamaan reaksi yang mungkin adalah 2N₂ + O₂ ⟶ 2N₂O

Pembuktian untuk memastikannya dapat digunakan data dari senyawa A (senyawa NO₂)
Untuk NO₂   ⟶ % N = {14 ÷ (14+32)} × 100% = 30,43 % ….. terbukti (sesuai data yang diberikan)
Untuk NO₂   ⟶ % O = {32 ÷ (14+32)} × 100% = 69,57 % ….. terbukti (sesuai data yang diberikan)

Perhitungan perbandingan untuk senyawa B (senyawa NO₂)
Untuk N₂O   ⟶ % N = {28 ÷ (28+16)} × 100% = 63,64 %
Untuk N₂O  ⟶ % O = {16 ÷ (28+16)} × 100% = 36,36 %
Jawaban:

1.                 Perbandingan massa X (N) dan Y (O) pada
massa N : massa O = 14 : 16 = 0,875 atau massa O : massa N = 16 : 14 = 1,14

2.                 Perkiraan rumus sesungguhnya X adalah N₂ dan Y adalah O₂

3.                 Persamaan reaksi yang mungkin untuk
Senyawa A : Reaksi: X + 2 Y ⟶ 2A persamaan reaksi yang mungkin N₂ + 2O₂ ⟶ 2NO₂
Senyawa B : Reaksi: 2X + Y ⟶ 2B persamaan reaksi yang mungkin 2N₂ + O₂ ⟶ 2N₂O

PEMBAHASAN SOAL NO. 2

2. Suatu wadah bervolume 2,125 L berisi gas belerang dioksida, dengan tekanan 0,75 atm pada 80 ^oC dihubungkan dengan pipa berkeran ke wadah lain berukuran 1,5 L berisi gas oksigen bertekanan 0,5 atm pada suhu yang sama.

i.                        Hitung fraksi mol gas belerang dioksida ketika kedua gas dicampurkan dengan membuka keran pipa penghubung kedua wadah (asumsikan kedua gas itu tidak bereaksi dan volum pipa penghubung kedua wadah tersebut dapat diabaikan) [3]

Pembahasan:

n SO₂ = PV/RT = (0,75 x 2,125) : (0,08206 x (273+80)) = 1,59375 : 28,96718 = 0,055 mol
n O₂ = PV/RT = (0,5 x 1,5) : (0,08206 x (273+80)) = 0,75 : 28,96718 = 0,025 mol
Fraksi mol SO₂ = n SO₂ : (n SO₂ + n O₂) = 0,055 : (0,055 + 0,026) = 0,68
Fraksi mol O₂ = 1 – 0,68 = 0,32

ii.                        Tentukan tekanan total setelah pencampuran gas dalam wadah tersebut [3]

Pembahasan:
P SO₂ dalam campuran = n SO₂ .R.T/V total = {0,055 x 0.08206 x (273+80)}/3,625 = 0,44 atm
P O₂ dalam campuran = n O₂ .R.T/V total = {0,026 x 0.08206 x (273+80)}/3,625 = 0,21 atm
P total = P SO₂ + P O₂ = 0,44 atm + 0,21 atm = 0,65 atm

iii.                        Hitung tekanan parsial gas belerang dioksida, setelah pencampuran tersebut [3]

Pembahasan:
P SO₂ = fraksi mol SO₂ x P total = 0,68 x 0,65 atm = 0,44 atm

iv.                        Jika dalam wadah tersebut terdapat katalis sehingga campuran gas bereaksi membentuk gas belerang trioksida, hitunglah fraksi mol gas belerang dioksida yang masih tersisa setelah terjadi reaksi sempurna [3]

v.                        Hitung pula tekanan total setelah reaksi berlangsung sempurna [3]

Pembahasan:
P SO₂ dalam campuran = n SO₂ .R.T/V total = {0,003 x 0.08206 x (273+80)}/3,625 = 0,03 atm
P SO₃ dalam campuran = n SO₃ .R.T/V total = {0,052 x 0.08206 x (273+80)}/3,625 = 0,41 atm
P total = P SO₂ + P SO₃ = 0,02586 atm + 0,41379 atm = 0,44 atm

vi.                        Tentukan volum gas belerang dioksida, SO₂, yang berefusi pada saat 0,50 cm³ belerang trioksida (telah berefusi keluar dari wadah tersebut) [3]

Difusi adalah proses perlahan pencampuran dua gas bersama-sama.
Efusi adalah proses yang terjadi ketika gas diizinkan untuk keluar dengan sendirinya dari wadah melalui lubang kecil.
Hukum Graham menyatakan tingkat di mana gas akan menyebar berbanding terbalik dengan akar kuadrat dari massa molar–nya. Ini berarti gas ringan menyebar dengan cepat dan gas berat menyebar perlahan-lahan.
Berdasarkan hukum Graham, bahwa laju efusi itu berbanding terbalik dengan akar kuadrat massa molarnya.

Pembahasan:
V_rmsSO₂/V_rmsSO₃ = √(Massa molar SO₃/Massa molar SO₂)
V_rmsSO₂/V_rmsSO₃ = √(80/64) = 1,12
Artinya laju efusi SO₂ 1,12 lebih cepat dari SO₃, jadi ketika volum 0,50 cm³ maka volume SO₂ yang berefusi sudah 1,12 x 0,50 cm³ = 0,56 cm³

PEMBAHASAN SOAL NO. 3

3.Barium peroksida dapat dibuat dari reaksi kesetimbangan barium oksida dengan oksigen pada tekanan dan temperatur tertentu. Sebanyak 1 g sampel yang mengandung campuran barium oksida dan barium peroksida direaksikan dengan asam sulfat, terbentuk 1,49 g endapan putih yang dipisahkan dari filtratnya. Filtrat tersebut dapat bereaksi dengan kalium iodida dalam asam menghasilkan 1,18 x 10^–3 mol iodin.

a.                 Tuliskan persamaan reaksi pembuatan barium peroksida [2]

2BaO_(s) + O_2(g) → 2BaO_2(s)

b.                 Tuliskan persamaan reaksi–reaksi yang mungkin terjadi antara sampel di atas dengan asam sulfat [4]

BaO + H₂SO₄ → BaSO₄ + H₂O
BaO₂ + H₂SO₄ → BaSO₄ + H₂O₂
BaO + BaO₂ + 2H₂SO₄ → 2BaSO₄ + H₂O₂ + H₂O

c.                 Tuliskan pula persamaan reaksi filtrat dengan kalium iodida dalam asam [4]

H₂O₂ + 2 I^– + K⁺ + 2H⁺ → I₂ + 2H₂O + K⁺

d.                 Bagaimana cara praktis mengetahui jumlah iodida yang dihasilkan pada reaksi tersebut? Tuliskan persamaan reaksi selengkapnya. [5]

Cara praktis mengetahui jumlah iodida adalah dengan membandingkan jumlah mol H₂O₂ berdasarkan perbandingan koefisien masing–masing zat. Dari persamaan reaksi dapat diketahui I₂ yang dihasilkan setara dengan jumlah mol H₂O₂.
H₂O₂ + 2 I^– + 2H⁺ → I₂ + 2H₂O

e.                 Hitung persen massa oksida–oksida yang terkandung dalam sampel tersebut [8]

Cara penyelesaian adalah berangkat dari jumlah mol iodin (1,18 x 10^–3 mol) dengan perbandingan koefisien reaksi.
Mol BaO₂ = mol H₂O₂ = mol I₂
Mol BaO₂ = 1,18 x 10^–3 mol
Massa BaO₂ = jumlah mol BaO₂ x massa molar BaO₂
Massa BaO₂ = 1,18 x 10^–3 mol x (137 + 2(16)) g/mol = 1,18 x 10^–3 mol x 169 g/mol = 0,2 g
Massa BaO = massa sampel – massa BaO₂ = 1 g – 0,2 g = 0,8 g
Persen massa BaO₂ dalam sampel = 0,2 g/1 g x 100% = 20%
Persen massa BaO dalam sampel = 0,8 g/1 g x 100% = 80%