Advertisements
Advertisements
प्रश्न
Why does distilled water not conduct electricity, whereas rain water does?
उत्तर १
Distilled water cannot conduct electricity because it does not contain ions, while rainwater conducts electricity because it contains ions due to the presence of dissolved salts in it.
उत्तर २
- Distilled water does not contain any ionic compounds in it.
- Whereas rainwater has a lot, more compounds.
- Rainwater has dissolved acidic gases, such as carbon dioxide, from the air, and that forms carbonic acid. This means that it has hydrogen ions and carbonate ions. Therefore, in the presence of acids, rainwater can conduct electricity.
APPEARS IN
संबंधित प्रश्न
While diluting an acid, why is it recommended that the acid should be added to water and not water to the acid?
Compounds such as alcohols and glucose also contain hydrogen but are not categorized as acids. Describe an activity to prove it.
Why do acids not show acidic behaviour in the absence of water?
What colour do the following indicators turn when added to a base or alkali (such as sodium hydroxide)?
(a) methyl orange
Fill in the blank in the following sentences:
Acids produce.......................... ions on dissolving in water.
What happens when dilute hydrochloric acid is added to sodium carbonate? Write a balanced chemical equation of the reaction involved.
What happens when carbon dioxide gas is passed through lime water for a short time?
Write equations of the reactions involved.
You have been provided with three test-bubes. One of these test-tubes contains distilled water and the other two contain an acidic and a basic solution respectively. If you are given only blue litmus paper, how will you identify the contents of each test-tube?
What is meant by strong bases and weak bases? Classify the following into strong bases and weak bases:
NH4OH, Ca(OH)2, NaOH, KOH, Mg(OH)2
Answer the following question.
Blue litmus solution is added to two test tubes A and B containing dilute HCl and NaOH solution respectively. In which test tube a colour change will be observed? State the colour change and give its reason.
In the experimental set-up to show that "the germinating seeds give out carbon dioxide", answer the following questions:
(i) Why do we keep the conical flask airtight?
(ii) Name the substance kept in the small test tube inside the conical flask. Write its role.
(iii) Why does water rise in the delivery tube?
Vinay observed that the stain of curry on a white shirt becomes reddish-brown when soap is scrubbed on it, but it turns yellow again when the shirt is washed with plenty of water. What might be the reason for his observation?
- Soap is acidic in nature
- Soap is basic in nature
- Turmeric is a natural indicator which gives reddish tinge in bases
- Turmeric is a natural indicator which gives reddish tinge in acids
In which of the following setups would the bulb glow?
Which of the following phenomena occur when a small amount of acid is added to water?
- Ionisation
- Neutralisation
- Dilution
- Salt formation
Which of the following is(are) true when HCl (g) is passed through water?
- It does not ionise in the solution as it is a covalent compound.
- It ionises in the solution
- It gives both hydrogen and hydroxyl ions in the solution
- It forms hydronium ion in the solution due to the combination of hydrogen ion with water molecule
Identify the correct representation of reaction occurring during chloralkali process
Salt A commonly used in bakery products on heating gets converted into another salt B which itself is used for the removal of hardness of water and a gas C is evolved. The gas C when passed through lime water, turns it milky. Identify A, B and C.
A metal carbonate X on reacting with an acid gives a gas which when passed through a solution Y gives the carbonate back. On the other hand, a gas G that is obtained at anode during electrolysis of brine is passed on dry Y, It gives a compound Z, used for disinfecting drinking water. Identity X, Y, G and Z.
- A compound 'A' with a molecular formula of \[\ce{C2H4O2}\] reacts with a base to give salt and water. Identify 'A', state its nature and the name of the functional group it possesses. Write chemical equation for the reaction involved.
- When the above stated compound 'A' reacts with another compound 'B' having molecular formula \[\ce{C2H6O}\] in the presence of an acid, a sweet smelling compound is 'C' formed.
- Identify 'B' and 'C'.
- State the role of acid in this reaction.
- Write chemical equation for the reaction involved.
