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When sodium chloride and metallic sodium are each dissolved in water

When sodium chloride and metallic sodium are each dissolved in water

  • A. both processes are exothermic
  • B. both processes are endothermic
  • C. the dissolution of metallic sodium is endothermic
  • D. the dissolution of metallic sodium is exothermic
  • E. the dissolution of sodium chloride is explosive
Correct Answer: Option D
Explanation

When small quantities of sodium metal is added to water, there is an exothermic reaction, and they react to form sodium hydroxide and hydrogen.


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Contributions (97)

Daviswag
5 years ago
the ansa is d. Reason:when a piece metallic sodium is dropped into a beaker of water,the sodium reacts with water acording to the eqation 2Na+2H2O---2NaOH+H2

.the sodium begins to melt @ a temperature of 97.8 deg. Celcius(melting point of sodium).there is a great amount of heat given off at this moment(exothermic reaction).the heat in the surroundings ignites d hydrogen gas given off in d reaction and causes it to burn with a bright flame.
ojodgreat
3 years ago
Here is an explanation:

this should be noted, when bond is formed, heat is released, since sodium is a very reactive metal, that form a bond when it reacts, therefore the dissolution of sodium metal in water result in the formation of a compound(SODIUM HYDROXIDE), and in the process, heat is released which is exothermic reaction.
Kamil054
5 years ago
D ans is "D" cos in NaCl, Cl always takes electrons nd in metallic sodium like for example zinc or Cu(copper) as a metallic element always gives out it's electrons for those elements who needs it. And exothermic reaction is d process in which heat(or we can say electrons) is released to d surroundins while Endothermic reaction in which heat or elecrons in absorbed in d surrounding.
ginikajoy
6 years ago
Na and K are very reactive metal they easily react wit water to liberate their oxides and hydrogen gas, remember in their salt form they react water to form their base and hydrochloric acid. Note the liberation of hydrogen gas is highly exothermic.
Zakirplus
6 years ago
Is reaction based on metal not endothermic, y exothermic. Since any reaction based on metal require heat.
blessingedet
3 years ago
i don't grasp
  • Chizzydarsec: mettalic sodium reacts with water and breaks down to form NaOH and H², and during the process of the breaking down there is release of energy which signifies that its an exothermic rxn
    Like 1    Dislike 0   1 month ago
korestine
6 years ago
option D actually the actually the correct answer bcosl metalic na undergoes exothermic rxn in both h2o and dil.h2so4
Mutty
6 years ago
d ansa is d bcos the soln of both tend to release heat into the environment, hence dey are exothermic.
Shenny Gee
1 year ago
It exothermic since it seems that when this reaction take place,heat is released to the environment.mind u environment this time means the system in which the reaction was experimented(by feeling its temperature e.g baker)
Stock
3 years ago
Na
danibams
6 years ago
Altho most of d contributns here re right,,bt i'd lik d admin to giv a convincn xplanatn,,coz if we tend to read al d contributns here one wud tend 2 be confused as to wich one we re to folow as d real answa,,,so admin pls shed more light on d real answ pls....
emmanuel204070
3 years ago
Nacl is used to melt ice faster
sholly22
1 year ago
can somebody please give me the formula?...
Olu2016
3 years ago
Na being an highly reactive element and 2nd in the activity series reacts vigorously with cold water forming metallic hydroxides and liberating hydrogen but effervescence(bubbling as an indication of evolution of heat) is not persived in the dissolution of sodium chloride in water
Debra miracle
4 years ago
D ansa is d in d sence dat when metals react they liberate heat in d suroudin that is exothermic,bt sodium chlorid hs already been posses wit chlorid,that is y both does nt involves exothermic.that is frm my view

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