Advertisements
Advertisements
प्रश्न
Give the characteristic tests for the following gases :
- CO2
- SO2
- O2
- H2
Advertisements
उत्तर
- CO2 gas : It is a colourless and odourless gas. When passed through lime water, it will initially become milky.
`underset("Lime water")("Ca"("OH")_2("aq")) + "CO"_2("g") -> "CaCO"_3("s") + "H"_2"O"("aq")`
The milkiness will disappear on passing the gas in excess.
`"CaCO"_3("s") + "CO"_2("g") + "H"_2"O" ("aq") -> underset("Colourless")("Ca"("HCO"_3)_2("aq"))` - SO2 gas : It is a colourless but a pungent smelling gas. The gas when passed through an acidified solution of potassium permanganate (pink) will decolourise it.
`underset("(Orange)")("K"_2"Cr"_2"O"_7) + 3"SO"_2 + "H"_2"SO"_4 -> "K"_2"SO"_4 + underset("(Light green)")("Cr"_2("SO"_4)_3) + "H"_2"O"` - Oxygen gas : The gas is a supporter of combustion. It can be tested by bringing a burning or smouldering match-stick near the mouth of the test tube from which the gas escapes. The match-stick will burn more brightly.
- Hydrogen gas : The gas itself is combustible. It will burn with a pop sound when a burning candle or match- stick is brought near it.
`2"H"_2("g") + "O"_2("g") -> 2"H"_2"O"("g")`
APPEARS IN
संबंधित प्रश्न
Write the balanced chemical equation for the following reaction.
\[\ce{Calcium hydroxide + Carbon dioxide → Calcium carbonate + Water}\]
How will you indicate the following effect in a chemical equation?
Exothermic reaction
What do you understand by endothermic reactions?
Zinc oxide reacts with carbon, on heating, to form zinc metal and carbon monoxide. Write a balanced chemical equation for this reaction. Name
- oxidising agent, and
- reducing agent,
in this reaction.
Write your observations and name the product when
Iron nails are added to an aqueous solution of copper sulphate.
Write word equation for the following skeletal equation:
\[\ce{Zn + HCl -> ZnCl2 + H2}\]
Balance the following chemical equation :
FeS + HCl → FeCl2 + H2S
Write symbolic representation for the following word equation and balance them :
Carbon + Oxygen → Carbon dioxide.
Write symbolic representation for the following word equation and balance them :
Iron + Sulphur → Iron sulphide.
Balance the following equation. Also name the product formed.
`"H"_2 +"CI"_2 → "HCI"`
Balance the following equation. Also name the product formed.
`"Na"+ "H"_2 "O" → "NaOH"+ "H"_2`
Write your observation and name the product when An aqueous solution of barium chloride is added to dilute sulphuric acid.
A student weighed some raisins and recorded the weight as ‘x’. She then soaked the raisins in distilled water. After about 2 hours she removed the raisins, wiped them dry and weighed them again, and recorded that as ‘y’. The percentage of water absorbed by raisins may be determined using the relationship.
Balance the equation stepwise.
H2S2O7(l) + H2O(l) → H2SO4(l)
State the information conveyed by the following equation:
Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2 ↑
What is the valency of :
carbon in CH4
Name the substance that is getting oxidised in the thermit process.
When a potassium iodide solution is added to a solution of lead (II) nitrate in a test tube, a precipitate is formed.
Write the balanced chemical equation for this reaction.
Give a balanced equation for addition of iron to copper [II] sulphate solution. State the change in colour seen.
Write a balanced equation for the following word equation:
Potassium bicarbonate → Potassium carbonate + Water + Carbon dioxide
