Advertisements
Advertisements
प्रश्न
Three experiments to study the process of rusting are given below. Observe the three test tubes and answer the following questions.
- Why the nail in the test tube 2 is not rusted?
- Why is the nail in the test tube 1 is rusted highly?
- Would the nail in the test tube 3 get rusted?
उत्तर
Essential requirements for corrosion are:
- Supply of oxygen
- Presence of water
- Material itself
- The nail in test tube 2 is not rusted because, in test tube 2, we take boiling water. So, all the dissolved oxygen is removed from the water and if the iron nail does not get a supply of oxygen then corrosion is not carried out.
- The nail in test tube 1 is rusted highly because, in test tube 1, the iron nail meets all the requirements that are essential for the corrosion process. That's Supply of oxygen is dissolved form, presence of water and material itself.
- The nail in test tube 3 is not rusted because calcium chloride is one of the best absorbents. So, it absorbs all the dissolved oxygen present in water. Hence, the corrosion process does not take place.
संबंधित प्रश्न
You are given a hammer, a battery, a bulb, wires and a switch.
- How could you use them to distinguish between samples of metals and non-metals?
- Assess the usefulness of these tests in distinguishing between metals and non-metals.
Fill in the blanks:
Iron is ________ reactive than copper.
Choose the correct answer from the options given below :
The two main metals in Bronze are:
(A) Copper and zinc
(B) Copper and lead
(C) Copper and nickel
(D) Copper and tin
Write the balanced chemical equation to prepare ammonia gas in the laboratory by using an alkali.
For the electro-refining of copper: What is the cathode made up of?
Give the name and formulae of two basic oxides.
Name two physical properties of carbon in which it's behaviour is not as expected from it's classification as non-metal.
How do non-metals react with oxygen? Explain with an example. Give equation of the reaction involved. What is the nature of the product formed? How will you demonstrate it?
Name a non-metal that is hardest naturally occurring substance
Name the metals present in the following alloys
Bronze
State the composition of given alloy:
Bronze
Define metal and non-metal on the basis of electron loss or gain.
Name a liquid non-metal.
Distinguish between metals and non metals on the basis of:
(i) ion formation, (ii) discharge of ions, (iii) nature of oxide formed, (iv) oxidizing and reducing property, (v) reaction with acids.
`Na _____ → Na^+`
Select from the following ist:
`Fe_2O_3, , NO, PbO, Mn_2O_7`
Neutral oxide ……………..
Name:
a metal whose oxide is reduced only by carbon
Give the effect of heat on metal oxides based on the activity series ?
Identify the odd term.
Name a metal which does not corrode easily.
Distinguish between the physical properties of metals and non-metals with reference to:
(a) lusture (b) malleability (c) ductility (d) tensile strength (e) sonority (f) conduction of heat and electricity (g) melting and boiling point (h) density.
With reference to the physical properties of metals and non-metals, state the following exception.
A metal which floats on water.
Complete the statement given below, by filling in the blank with the correct word:
A metal which floats on water _____
Select the appropriate option for the following statement:
The element which is noble gas and radioactive in nature.
Identify who I am!
Carbon allotropes- _______
Identify who I am!
Metal in Liquid state- _______
Pencil lead contains
Paheli bought a statue made up of copper. To her surprise, it acquired a dull green coating after a couple of months. Explain the reason.
