Advertisements
Advertisements
प्रश्न
Which of the following is(are) an endothermic process(es)?
- Dilution of sulphuric acid
- Sublimation of dry ice
- Condensation of water vapours
- Evaporation of water
विकल्प
(i) and (iii)
(ii) only
(iii) only
(ii) and (iv)
Advertisements
उत्तर
(ii) and (iv)
Explanation -
Both sublimation of dry ice (ii) and evaporation of water (iv) are of endothermic nature.
APPEARS IN
संबंधित प्रश्न
Write balanced chemical equations for the following word equation:
Sodium + chlorine → Sodium chloride
Define chemical reaction.
Balance the following equation. Also name the products formed.
`CO _2 + C → CO`
Balance the following equation:
\[\ce{C + H2SO4->CO2 + H2O + SO2}\]
Balance the following equation:
\[\ce{Fe2O3 + CO->Fe + CO2}\]
Underline the incorrectly balanced compound equation and rewrite the correct equation.
\[\ce{FeS + 2HCl + 2FeCl2 + H2S}\]
Balance the following important equation:
ZnS + O2 → ZnO + SO2
Balance the following important equation:
Fe + HCl → FeCl2 + H2
Balance the following important equation:
Na2CO3 + HCl → NaCl + H2O + CO2
Balance the following important equation:
K2Cr2O7 + HCl → KCl + CrCl3 + H2O + Cl2
Balance the following important equation:
NH4OH + H2SO4 → (NH4)2SO4 + H2O
Balance the following important equation:
Ca(HCO3)2 + HNO3 → Ca(NO3)2 + H2O + CO2
Balance the following important equation:
Cu + HNO3 (conc.) → Cu(NO3)2 + H2O + NO2
Balance the following important equation:
Cu + H2SO4 (conc.) → CuSO4 + H2O + SO2
A teacher gave two test tubes to the students, one containing water and the other containing sodium hydroxide. She asked them to identify the test tube containing sodium hydroxide solution. Which one of the following can be used for identification?
Magnesium ribbon is rubbed before burning because it has a coating of ____________.
In the double displacement reaction between aqueous potassium iodide .and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?
Write the balanced chemical equations for the following reactions and identify the type of reaction in each case.
- Iron (III) oxide reacts with aluminum and gives molten iron and aluminum oxide.
- Magnesium ribbon is burnt in an atmosphere of nitrogen gas to form solid magnesium nitride.
- Chlorine gas is passed in an aqueous potassium iodide solution to form potassium chloride solution and solid iodine.
- Ethanol is burnt in air to form carbon dioxide, water and releases heat.
Which among the following change is exothermic or endothermic in nature?
Dilution of sulphuric acid
A magnesium ribbon is burnt in oxygen to give a white compound ‘X’ accompanied by emission of light. If the burning ribbon is now placed in an atmosphere of nitrogen, it continues to burn and forms a compound ‘Y’.
- Write the chemical formulae of X and Y.
- Write a balanced chemical equations when X and Y are dissolved in water.
