Advertisements
Advertisements
Question
The metal M reacts vigorously with water to form a solution S and a gas G. The solution S turns red litmus to blue whereas gas G, which is lighter than air, burns with a pop sound. Metal M has a low melting point and it is used as a coolant in nuclear reactors.
(a) What is metal M?
(b) What is solution S? Is it acidic or alkaline?
(c) What is gas G?
(d) Write a balanced chemical equation for the reaction which takes place when metal M reacts with water.
(e) Is this reaction exothermic or endothermic?
Advertisements
Solution
(a) Metal M is sodium (Na), which is used as a coolant in nuclear reactors.
(b) Solution S is sodium hydroxide solution (NaOH). It is alkaline, it turns red litmus to blue.
(c) Gas G is hydrogen gas, which is lighter than air.
(d) 2Na (s) + 2H2O (l) → 2NaOH (aq) + H2 (g) + HEAT
(e) This reaction is exothermic because it releases excessive heat.
APPEARS IN
RELATED QUESTIONS
Translate the following statement into chemical equation and then balance it.
Hydrogen gas combines with nitrogen to form ammonia
Balance the given equation:
NH3 + CuO 
Cu +N2 +H2O
When hydrogen is passed over copper oxide, copper and steam are formed. Write a balanced equation for this reaction and state which of the chemicals are compounds.
What happens when silver nitrate solution is added to sodium chloride solution?
Write the equation for the reaction which takes place.
Write symbolic representation for the following word equation and balance them :
Calcium carbonate → Calcium oxide + Carbon dioxide.
Balance the following equation. Also name the product formed.
N2 + H2 → NH3
Balance the following equation. Also name the product formed.
FeCI2 + CI2 → FeCI3
Write your observation and name the product when zinc reacts with dilute hydrochloric acid.
While performing the experiment with raisins to determine the percentage of water absorbed by them, a student made following measurements:
Mass of water in the beaker = 40 g
Mass of raisins before soaking = 5 g
Mass of raisins after soaking for 2 hours = 8 g
Mass of water left in the beaker after the experiment = 35 g
The percentage of water absorbed by raisins is:
Balance the following equation:
Zn + KOH → K2ZnO2 + H2
Balance the following equation:
Fe2O3 + CO → Fe + CO2
Balance the following equation:
Zn + HNO3 `→` Zn(NO3)2 + H2O + NO2
\[\ce{MnO2 + 4HCl -> MnCl2 + 2H2O + Cl2}\]
0.02 moles of pure MnO2 is heated strongly with conc. HCl. Calculate the volume of chlorine gas formed at S.T.P.
Write word equation for the following molecular equation:
\[\ce{NH3 [g] + HCl [g] ⇌ NH4Cl [s]}\]
Word equation:
State which characteristic is observed in the above reaction.
Give an-example of a similar above characteristic, seen between two other gaseous reactants.
Write word equation for the following molecular equation:
\[\ce{CuSO4 + 2NaOH -> Na2SO4 + Cu(OH)2↓}\]
Word equation:
State the colour of the products.
A chemical reaction is generally accompanied by certain external indications or characteristics. These include – change of – (a) colour (b) state (c) smell (d) evolution of gas (e) formation of precipitate (f) evolution or absorption of heat. With reference to change of colour – state the change in colour seen when the following are heated – lead [IV] oxide.
In certain reaction an insoluble solid called precipitate is formed. State the colour and name of the precipitate formed in the following reaction involving addition of:
Copper [II] sulphate to sodium hydroxide.
Balance the following simple equation:
KHCO3 → K2CO3 + H2O + CO2
Write a balanced equation for the following word equation:
Aluminium + Oxygen → Aluminium oxide
Give a balanced equation by the partial equation method, [steps are given below].
Oxidation of Lead [II] Sulphide by Ozone
- Ozone first decomposes to give molecular oxygen & nascent oxygen.
- Nascent oxygen then oxidises lead [II] sulphide to lead [II] sulphate.
