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How is metal refined by electrolysis

Posted by Pinky Agarwal 7 years, 1 month ago

1 answers

Yogita Ingle 7 years, 1 month ago

It is the process of refining of metal in which impure metal is made the anode and a thin strip of pure metal is made the cathode. A solution of metal salt is used as an electrolyte. The apparatus is shown in the figure given below. When electric current is passed through the electrolyte, the impure metal from the anode is dissolved in the electrolyte and an equal amount of pure metal from the electrolyte is deposited on the cathode. The soluble impurities go into the solution whereas the insoluble impurities settle down at the bottom of the anode which is known as anode mud. Following diagram shows the electrolytic refining of copper in which anode is impure copper and cathode is thin strip of pure copper while the electrolyte used is the copper sulphate solution.

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What happens in Electrolysis of NaCl?

Posted by Pinky Agarwal 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

Electrolysis of common salt solution: When electricity is passed through the salt solution, four types of ions, ie, sodium, chlorine, hydrogen, hydrogen ions are produced. Hydrogen ions discharge at cathode whereas chlorine ions are discharged at the anode. Now if the electrodes are immersed in water and current is passed, bubbles of oxygen gas is liberated at cathode

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What is chemical effect of current

Posted by Pinky Agarwal 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Yogita Ingle 7 years, 1 month ago

When electric current is passed through a conducing solution, some chemical reaction takes place in the solution. This is called chemical effect of electric current. Some of the chemical effects of electric current are as follows:

Bubbles of gas may be formed at electrodes.
Deposits of metal may be seen on electrodes.
Change of colour of solution may occur.

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Sodium is kept in kerosene while phosphorus is kept in water

Posted by Surbhi Jain 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Prathiksha Prabakaran 7 years, 1 month ago

Sodium reacts with oxygen more vigoursly than phosphorus

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Copper bottomed utensils are made up for cooking

Posted by Surbhi Jain 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 6 years, 1 month ago

Copper bottomed utensils are made up for cooking because copper is an excellent conductor of heat and have the highest thermal conductivity,

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Metal are used to make string of musical instruments give reason

Posted by Surbhi Jain 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Neharika Varshney 7 years, 1 month ago

They hve the property of sonrousity in which ringing sound is produce when hit with any other metal

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I heard that magnesium is found in plant. In what form is it found in them

Posted by Kanhaiya Jha 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 6 years, 1 month ago

Magnesium is a building block of the Chlorophyll, which makes leaves appear green. Hence, it plays an important role in photosynthesis.

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Khani me mote mote kya he

Posted by Nandani Kumari 5 years, 11 months ago

CBSE > Class 08 > Science

1 answers

Richa Shree 7 years, 1 month ago

Kahani me mote mote baccho ke liye hai

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When electric charge move ,they constitution

Posted by Khushi Khan 7 years, 1 month ago

CBSE > Class 08 > Science

0 answers

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Is there any way to remember amoeba's function

Posted by Prathiksha Prabakaran 5 years, 11 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

How can we see object?

Posted by Konika Monika 7 years, 1 month ago

CBSE > Class 08 > Science

2 answers

Mayil Vishnu 7 years, 1 month ago

Through our eyes

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Konika Monika 7 years, 1 month ago

Because reflection

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How the paper makes??? Told in detail???

Posted by Harsh Rawat 7 years, 1 month ago

CBSE > Class 08 > Science

0 answers

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Suppose you are outside your home and an earth quake strikes what precaution would you take to protect yourself ?explain in detail

Posted by Super Stare 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Umme Kulsoom 7 years, 1 month ago

I am outside of home an earthquake strikes precaution I would take are list below : I. Find a clear sport away from tall buildings, tress and overhead power lines drop to the ground. II. If you are in car or bus do not come out ask the driver to drive slowly to a clear spot away from tall tree. Do not come out till the tremors stop

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Who was the first man on the earth?

Posted by Ashmeet Singh 7 years, 1 month ago

CBSE > Class 08 > Science

2 answers

Krish Sreeniwas 7 years, 1 month ago

That time there were no names for the man and they were known as monkeys or purvag they used to roam

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Kajal Ranjan 7 years, 1 month ago

Chiranjivi Kumar Ranjan

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Does pure water conduct electricity if not what can we do to make it conducting

Posted by Aashish Rai 7 years, 1 month ago

CBSE > Class 08 > Science

2 answers

Ishank Vaishnav 7 years, 1 month ago

No pure water does no conduct electricity to make it conduting we dissolved acid base and salt in it

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Kajal Ranjan 7 years, 1 month ago

We con dissolve any acid,base and salt in water

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Why water is not bu rn

Posted by Anish Kumar 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Kajal Ranjan 7 years, 1 month ago

Because it evoprote in air before burning

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One of the methods of cleaning waste gases coming out of industries is to pass them through a scrubber, which has screens containing solvents. Do you think oxides of nitrogen and sulphur can be removed this way? please meritnation , try to give answer a bit fast..its urgent.

Posted by Pankaj Kumar 7 years, 1 month ago

CBSE > Class 08 > Science

0 answers

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Industrial waste removed by scruber of nitrogen and sulphur is it correct?

Posted by Pankaj Kumar 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Meghna Thapar 5 years, 9 months ago

A post-treatment process is therefore required to remove nitrogen and phosphorus from the effluent. However, because such effluents contain only small amounts of organic compounds, a carbon source must be added to remove the nitrogen. There are two steps for removing nitrogen in biological treatment: nitrification and denitrification. In this process, nitrifiers, including ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB), convert total ammonia (free ammonia and un-ionized ammonia) to nitrate. Power stations generate electricity. By reducing electricity use, everyone can reduce the emission of air pollutants from power stations. Sulfur dioxide may be removed from the waste gases by a process called gas scrubbing.

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Name the gases released by the reaction between : a.metal and acid- b.metal and base-

Posted by Kavya Keerti 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Prathiksha Prabakaran 7 years, 1 month ago

Both reaction produce hydrogen gas

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Father of biology

Posted by Ajeetparashar Ajeet Parashar 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Mithali Pattanaik 7 years, 1 month ago

Aristotle

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What is blind spot

Posted by Kushagra Shreyas 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Gaurav Seth 7 years, 1 month ago

The region of the retina where the optic nerve enters the eye is called blind spot. This portion of the eye lacks light-detecting photo-receptor cells.

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In which female reproductive organ does the embryo get embedded

Posted by Piyush Sharma 7 years, 1 month ago

CBSE > Class 08 > Science

2 answers

Yogita Ingle 7 years, 1 month ago

In walls of the uterus. The embryo, once attached to uterus gradually develops various body parts such as hands, legs, head, eyes, etc into an embryo.

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Shresth 7 years, 1 month ago

Uterus

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Name the unit in which the calorific value of a fuel is expressed

Posted by Sneha Verma 7 years, 1 month ago

CBSE > Class 08 > Science

2 answers

Amazing Varshith Pro 7 years, 1 month ago

Kj ( kilo joule ) / kg

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Shresth 7 years, 1 month ago

Kj/kg

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Distinguish between endemic species and endangered species

Posted by Kakul Manav 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Aryan Raj 7 years, 1 month ago

Endemic species are those species which are found exclusively in the particular region. But the endangered species are those species which are in the verge of extinsion

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Write types of combustion

Posted by Ekansh Chaudhary 7 years, 1 month ago

CBSE > Class 08 > Science

2 answers

Vrinda Chhabra 7 years, 1 month ago

(i) rapid combustion (ii) spontaneous combustion (iii) explosion

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Gurwinder Sandhu 7 years, 1 month ago

Micro gravity Micro combustion Rapid combustion Spotaneous

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What is thunder and lighting ?

Posted by Aasima S 7 years, 1 month ago

CBSE > Class 08 > Science

1 answers

Kavya Keerti 7 years, 1 month ago

When Very huge opposite charged clouds strike each other,then huge light will be produced known as LIGHTNING and lightning when passes through the air of atmosphere,large sound will be produced called as THUNDER

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What is shifting cultivation?

Posted by Jahanvi Mishra 7 years, 1 month ago

CBSE > Class 08 > Science