0 votes
225 views
in Chapter 8: Elements of Group 1 and 2 by (98.9k points)
edited
Lithium floats an water while sodium floats and catches fire when put in water.

1 Answer

0 votes
by (98.9k points)
selected by
 
Best answer

When lithium and sodium react with water, hydrogen gas is released. Due to these hydrogen gas bubbles, lithium and sodium floats on water.
eg. 2Na + 2H2O → 2Na+ + 2OH + H2

The reactivity of group 1 metals increases with increasing atomic radius and lowering of ionization enthalpy down the group.

Thus, sodium having lower ionization enthalpy, is more reactive than lithium.

Hence, lithium reacts slowly while sodium reacts vigorously with water.

Since the reaction of sodium with water is highly exothermic, it catches fire when put in water.

Related questions

0 votes
1 answer 182 views

Doubtly is an online community for engineering students, offering:

  • Free viva questions PDFs
  • Previous year question papers (PYQs)
  • Academic doubt solutions
  • Expert-guided solutions

Get the pro version for free by logging in!

5.7k questions

5.1k answers

108 comments

554 users

...