hydrogen bromide has a melting point of -87 deg celsius and a
boiling point of -67 deg celsius. it dissolbes in water to form an
acidic solution. describe what is seen when chlorine is bubbled
through the solution.
the answer writes solution turns yellow. but i think it should
be reddish brown. after all , isnt this a displacement reaction and
chlorine displaces bromine? please check for discrepancies.
next. a student carried out some experiments to compare the
relative strengths f dilute ethanoic acid and dilute hydrochloric
acid. name a solid substance that will react with both acids.
describe what you will see during the reaction.
what do you use? metal? if yes, then would the reaction be
faster with HCl because it is a stronger acid and is fully ionised,
thereby having a higher amount of H + ions.
please help ASAP because i still have got to clear my humans
studying for tomorrow. thanks!
>>> hydrogen bromide has a melting point of -87
deg celsius and a boiling point of -67 deg celsius. it dissolbes in
water to form an acidic solution. describe what is seen when
chlorine is bubbled through the solution.
the answer writes solution turns yellow. but i think it should
be reddish brown. after all , isnt this a displacement reaction and
chlorine displaces bromine? please check for discrepancies.
<<<
Correct.
FYI, displacement is a redox reaction. Chlorine is a stronger
oxidizing agent compared to bromine, and hence will displace
bromide ions (which is the reducing agent) from solution. The
reason has to do with distance between nucleus and valence shell,
and therefore, down the Group, a differential readiness
to gain electrons (for halogens) and lose electrons (for halide
ions).
>>> next. a student carried out some experiments to
compare the relative strengths f dilute ethanoic acid and dilute
hydrochloric acid. name a solid substance that will react with both
acids. describe what you will see during the reaction.
what do you use? metal? if yes, then would the reaction be
faster with HCl because it is a stronger acid and is fully ionised,
thereby having a higher amount of H + ions. <<<
Correct. But, both being monoprotic acids (aka monobasic acids),
they have the same no. of acidic protons (H+ ions). It's the
molarity (concentration) of protons (H+ ions) for which strong
acids is much higher than weak acids, hence rate of
reaction to produce the gas will be faster.
Exam Tips :
1) When answering the question, do include relevant
equations.
2) Specify a reactive metal (eg. magnesium). Otherwise, use
carbonates.
3) State that a gas syringe is used to collect gas evolved; and
rate of gas evolved over time can be calculated for comparison.