Tag: chemical effects of electric current

Quizzes (7) Questions (37)

Questions Related to chemical effects of electric current

Multiple choice physics chemical effects of electric current does liquid conduct electricity? liquids conduct electricity do liquids conduct electricity?

Water obtained from which of the following sources is a good conductor of electricity?

  1. Tap

  2. Ponds

  3. Wells

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The water that we get from sources such as taps, hand pumps, wells and ponds is not pure. It may contain several salts dissolved in it. Small amounts of mineral salts are naturally present in it. This water is thus a good conductor of electricity.

Multiple choice physics chemical effects of electric current does liquid conduct electricity? liquids conduct electricity do liquids conduct electricity?

Which of the following is a good conductor of electricity?

  1. Sugar solution

  2. Oil

  3. Distilled water

  4. Tap water
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The water that we get from sources such as taps, hand pumps, wells and ponds is not pure. It may contain several salts dissolved in it. Small amounts of mineral salts are naturally present in it. This water is thus a good conductor of electricity.

Multiple choice chemistry chemical effects of electric current applications of electrolysis electroplating extraction of metals by electrolysis

If $Zn/Zn^{+2}$ electrode is diluted 100 times then the change in electromotive force will be :-

  1. increases of 59 mV

  2. decreases of 59 mV

  3. increases of 29.5 mV

  4. decreases of 29.5 mV
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Using the Nernst equation: E = E_cell - (0.059/n) * log(1/[Zn+2]). Diluting 100 times increases the concentration of the denominator in the log term, making the log term more negative, which increases the overall potential by (0.059/2) * log(100) = 0.059 V = 59 mV.

Multiple choice chemistry chemical effects of electric current applications of electrolysis electroplating extraction of metals by electrolysis

The process of depositing thin layer of a metal over an another metal with a help of electric current is called :

  1. electrorefining

  2. electroplating

  3. thermoplating

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Electroplating is the process of plating one metal onto another, for decorative purposes or to prevent corrosion of a metal. 

Multiple choice chemistry chemical effects of electric current applications of electrolysis electroplating extraction of metals by electrolysis

The electrical process of coating an inexpensive conductor with a metal is called electroplating.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Electroplating is a process that uses electric current to deposit/reduce dissolved metal cations so that they form a thin coherent metal coating on an electrode.

It is used to coat a relatively mundane metal, such as copper, with a thin layer of another, more precious metal, such as gold or silver. 

Hence, option $\text{A}$ is correct.
Multiple choice chemistry chemical effects of electric current applications of electrolysis electroplating extraction of metals by electrolysis

Chromium plating is done to make the object scratch proof and appear shiny.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chromium plating is a technique of electroplating in which a thin layer of chromium is coated onto a metal object. The layer is decorative (shiny), provide corrosion resistance, ease cleaning procedures, and increase surface hardness (scratch resistance).


Hence, option A is correct.