Curd and other sour substances contain acids. Therefore, when they are kept in brass and copper vessels, the metal reacts with the acid to liberate hydrogen gas and harmful products, thereby spoiling the food. Metal + Acid β Salt + Hydrogen gas ππ+2π»βππββ ππ(ππβ)2 +2π»β
Curd and other sour substances contain acids. Therefore, when they are kept in brass and copper vessels, the metal reacts with the acid to liberate hydrogen gas and harmful products, thereby spoiling the food.
Metal + Acid β Salt + Hydrogen gas
ππ+2π»βππββ ππ(ππβ)2 +2π»β
If the colour of red litmus paper gets changed to blue, then it is a base and if there is no colour change, then it is either acidic or neutral. Thus, basic solution can be easily identified. Let us mark the three test tubes as A, B, and C. A drop of the solution in A is put on the red litmus paper.Read more
If the colour of red litmus paper gets changed to blue, then it is a base and if there is no colour change, then it is either acidic or neutral. Thus, basic solution can be easily identified.
Let us mark the three test tubes as A, B, and C. A drop of the solution in A is put on the red litmus paper. Same is repeated with solution B and C.
If either of them changes colour to blue, then it is basic. Therefore, out of three, one is eliminated.
Out of the remaining two, any one can be acidic or neutral. Now a drop of basic solution is mixed with a drop of each of the remaining two solutions separately and then the nature of the drops of the mixtures is checked.
If the colour of red litmus turns blue, then the second solution is neutral and if there is no change in colour, then the second solution is acidic.
This is because acidic and basic solutions neutralize each other. Hence, we can distinguish between the three types of solutions.
Important uses of Washing Soda β’ Sodium carbonate (washing soda) is used in glass, soap and paper industries. β’ It is used in the manufacture of sodium compounds such as borax. β’ Sodium carbonate can be used as a cleaning agent for domestic purposes. β’ It is used for removing permanent hardness of wRead more
Important uses of Washing Soda
β’ Sodium carbonate (washing soda) is used in glass, soap and paper industries.
β’ It is used in the manufacture of sodium compounds such as borax.
β’ Sodium carbonate can be used as a cleaning agent for domestic purposes.
β’ It is used for removing permanent hardness of water.
Important uses of Baking Soda
β’ It is used to make bread or cake soft and spongy.
β’ It is used as antacids. Being alkaline, it neutralises excess acid in the stomach and provides relief.
β’ It is also used in soda-acid fire extinguishers.
Plaster of Paris (POP) should be stored in a moisture-proof container because Plaster of Paris, a powdery mass, absorbs water (moisture) to form a hard solid known as gypsum. CaSOβ.1/2HβO+ 3/2HβO β CaSOβ.2HβO
Plaster of Paris (POP) should be stored in a moisture-proof container because Plaster of Paris, a powdery mass, absorbs water (moisture) to form a hard solid known as gypsum.
(a) The milkman shifts the pH of the fresh milk from 6 to slightly alkaline because in alkaline condition, so that it takes longer time to be spoiled (become acidic). (b) Since this milk is slightly basic than usual milk, acids produced to set the curd are neutralized by the base. Therefore, it takeRead more
(a) The milkman shifts the pH of the fresh milk from 6 to slightly alkaline because in alkaline condition, so that it takes longer time to be spoiled (become acidic).
(b) Since this milk is slightly basic than usual milk, acids produced to set the curd are neutralized by the base. Therefore, it takes a longer time for the curd to set.
The pH of milk is 6. As it changes to curd, the pH will reduce because curd is acidic in nature. The acids present in it decrease the pH. For more answers visit to website: https://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/
The pH of milk is 6. As it changes to curd, the pH will reduce because curd is acidic in nature. The acids present in it decrease the pH.
The fizzing will occur strongly in test tube A, in which hydrochloric acid (HCl) is added. This is because HCl is a stronger acid than CHβCOOH and therefore produces hydrogen gas at a faster speed due to which fizzing occurs. For more answers visit to website: https://www.tiwariacademy.com/ncert-solRead more
The fizzing will occur strongly in test tube A, in which hydrochloric acid (HCl) is added. This is because HCl is a stronger acid than CHβCOOH and therefore produces hydrogen gas at a faster speed due to which fizzing occurs.
(a) Neutral β Solution D with pH 7 (b) Strongly alkaline β Solution C with pH 11 (c) Strongly acidic β Solution B with pH 1 (d) Weakly acidic β Solution A with pH 4 (e) Weakly alkaline β Solution E with pH 9 The pH can be arranged in the increasing order of the concentration of hydrogen ions as: 11Read more
(a) Neutral β Solution D with pH 7
(b) Strongly alkaline β Solution C with pH 11
(c) Strongly acidic β Solution B with pH 1
(d) Weakly acidic β Solution A with pH 4
(e) Weakly alkaline β Solution E with pH 9
The pH can be arranged in the increasing order of the concentration of hydrogen ions as: 11 < 9 < 7 < 4 < 1
Acids do not show acidic behaviour in the absence of water because the dissociation of hydrogen ions (π»+) from an acid occurs in the presence of water only. It is the hydrogen ions (π»+) that are responsible for the acidic behaviour. For more answers visit to website: https://www.tiwariacademy.com/ncRead more
Acids do not show acidic behaviour in the absence of water because the dissociation of hydrogen ions (π»+) from an acid occurs in the presence of water only. It is the hydrogen ions (π»+) that are responsible for the acidic behaviour.
Distilled water is a pure form of water not containing any ionic species. Therefore, it does not conduct electricity. Rain water, being an impure form of water, contains many ionic species (dissolved in air) such as acids and therefore it conducts electricity. For more answers visit to website: httpRead more
Distilled water is a pure form of water not containing any ionic species. Therefore, it does not conduct electricity. Rain water, being an impure form of water, contains many ionic species (dissolved in air) such as acids and therefore it conducts electricity.
Why should curd and sour substances not be kept in brass and copper vessels?
Curd and other sour substances contain acids. Therefore, when they are kept in brass and copper vessels, the metal reacts with the acid to liberate hydrogen gas and harmful products, thereby spoiling the food. Metal + Acid β Salt + Hydrogen gas ππ+2π»βππββ ππ(ππβ)2 +2π»β
Curd and other sour substances contain acids. Therefore, when they are kept in brass and copper vessels, the metal reacts with the acid to liberate hydrogen gas and harmful products, thereby spoiling the food.
See lessMetal + Acid β Salt + Hydrogen gas
ππ+2π»βππββ ππ(ππβ)2 +2π»β
You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?
If the colour of red litmus paper gets changed to blue, then it is a base and if there is no colour change, then it is either acidic or neutral. Thus, basic solution can be easily identified. Let us mark the three test tubes as A, B, and C. A drop of the solution in A is put on the red litmus paper.Read more
If the colour of red litmus paper gets changed to blue, then it is a base and if there is no colour change, then it is either acidic or neutral. Thus, basic solution can be easily identified.
Let us mark the three test tubes as A, B, and C. A drop of the solution in A is put on the red litmus paper. Same is repeated with solution B and C.
If either of them changes colour to blue, then it is basic. Therefore, out of three, one is eliminated.
Out of the remaining two, any one can be acidic or neutral. Now a drop of basic solution is mixed with a drop of each of the remaining two solutions separately and then the nature of the drops of the mixtures is checked.
If the colour of red litmus turns blue, then the second solution is neutral and if there is no change in colour, then the second solution is acidic.
This is because acidic and basic solutions neutralize each other. Hence, we can distinguish between the three types of solutions.
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/
Give two important uses of washing soda and baking soda
Important uses of Washing Soda β’ Sodium carbonate (washing soda) is used in glass, soap and paper industries. β’ It is used in the manufacture of sodium compounds such as borax. β’ Sodium carbonate can be used as a cleaning agent for domestic purposes. β’ It is used for removing permanent hardness of wRead more
Important uses of Washing Soda
β’ Sodium carbonate (washing soda) is used in glass, soap and paper industries.
β’ It is used in the manufacture of sodium compounds such as borax.
β’ Sodium carbonate can be used as a cleaning agent for domestic purposes.
β’ It is used for removing permanent hardness of water.
Important uses of Baking Soda
β’ It is used to make bread or cake soft and spongy.
β’ It is used as antacids. Being alkaline, it neutralises excess acid in the stomach and provides relief.
β’ It is also used in soda-acid fire extinguishers.
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/
Plaster of Paris should be stored in a moisture-proof container. Explain why?
Plaster of Paris (POP) should be stored in a moisture-proof container because Plaster of Paris, a powdery mass, absorbs water (moisture) to form a hard solid known as gypsum. CaSOβ.1/2HβO+ 3/2HβO β CaSOβ.2HβO
Plaster of Paris (POP) should be stored in a moisture-proof container because Plaster of Paris, a powdery mass, absorbs water (moisture) to form a hard solid known as gypsum.
CaSOβ.1/2HβO+ 3/2HβO β CaSOβ.2HβO
See lessA milkman adds a very small amount of baking soda to fresh milk.
(a) The milkman shifts the pH of the fresh milk from 6 to slightly alkaline because in alkaline condition, so that it takes longer time to be spoiled (become acidic). (b) Since this milk is slightly basic than usual milk, acids produced to set the curd are neutralized by the base. Therefore, it takeRead more
(a) The milkman shifts the pH of the fresh milk from 6 to slightly alkaline because in alkaline condition, so that it takes longer time to be spoiled (become acidic).
(b) Since this milk is slightly basic than usual milk, acids produced to set the curd are neutralized by the base. Therefore, it takes a longer time for the curd to set.
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/
Fresh milk has a pH of 6. How do you think the pH will change as it turns into curd? Explain your answer.
The pH of milk is 6. As it changes to curd, the pH will reduce because curd is acidic in nature. The acids present in it decrease the pH. For more answers visit to website: https://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/
The pH of milk is 6. As it changes to curd, the pH will reduce because curd is acidic in nature. The acids present in it decrease the pH.
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/
Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCl) is added to test tube A, while acetic acid (CH3COOH) is added to test tube B. Amount and concentration taken for both the acids are same. In which test tube will the fizzing occur more vigorously and why?
The fizzing will occur strongly in test tube A, in which hydrochloric acid (HCl) is added. This is because HCl is a stronger acid than CHβCOOH and therefore produces hydrogen gas at a faster speed due to which fizzing occurs. For more answers visit to website: https://www.tiwariacademy.com/ncert-solRead more
The fizzing will occur strongly in test tube A, in which hydrochloric acid (HCl) is added. This is because HCl is a stronger acid than CHβCOOH and therefore produces hydrogen gas at a faster speed due to which fizzing occurs.
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/
Five solutions A,B,C,D and E when tested with universal indicator showed pH as 4,1,11,7 and 9, respectively. Which solution is
(a) Neutral β Solution D with pH 7 (b) Strongly alkaline β Solution C with pH 11 (c) Strongly acidic β Solution B with pH 1 (d) Weakly acidic β Solution A with pH 4 (e) Weakly alkaline β Solution E with pH 9 The pH can be arranged in the increasing order of the concentration of hydrogen ions as: 11Read more
(a) Neutral β Solution D with pH 7
(b) Strongly alkaline β Solution C with pH 11
(c) Strongly acidic β Solution B with pH 1
(d) Weakly acidic β Solution A with pH 4
(e) Weakly alkaline β Solution E with pH 9
The pH can be arranged in the increasing order of the concentration of hydrogen ions as: 11 < 9 < 7 < 4 < 1
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/
Why do acids not show acidic behaviour in the absence of water?
Acids do not show acidic behaviour in the absence of water because the dissociation of hydrogen ions (π»+) from an acid occurs in the presence of water only. It is the hydrogen ions (π»+) that are responsible for the acidic behaviour. For more answers visit to website: https://www.tiwariacademy.com/ncRead more
Acids do not show acidic behaviour in the absence of water because the dissociation of hydrogen ions (π»+) from an acid occurs in the presence of water only. It is the hydrogen ions (π»+) that are responsible for the acidic behaviour.
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/
Why does distilled water not conduct electricity, whereas rain water does?
Distilled water is a pure form of water not containing any ionic species. Therefore, it does not conduct electricity. Rain water, being an impure form of water, contains many ionic species (dissolved in air) such as acids and therefore it conducts electricity. For more answers visit to website: httpRead more
Distilled water is a pure form of water not containing any ionic species. Therefore, it does not conduct electricity. Rain water, being an impure form of water, contains many ionic species (dissolved in air) such as acids and therefore it conducts electricity.
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-10/science/chapter-2/