Boiling-point is the point of a pure liquid matter starts to evaporate and change into gaseous phase. It is where the set of conditions such as the pressure and temperature enough to do so. Boiling-point elevation, on the other hand, is the phenomenon of which the boiling point of a pure liquid matter is elevated because of the dissolved substances. A great example would be the boiling point of a distilled water (pure water) which is lesser than the boiling point of a sea water because of the dissolved salts. A pure water boils at 100°C at atmospheric pressure while a salt water boils at higher temperature than 100°C at the same pressure. Thus, the answer is D.
<span>B. energy
hope it helps
</span>
C. Accelerating should be the correct onw
Answer and Explanation:
Aspirin is odorless, but when left exposed to air in the environment, it gradually hydrolyzes into salicylic acid and acetic acid as that is the precursor for synthesizing Aspirin.
Using this hydrolyzed aspirin for titration would not be advised, because it would affect the reading of the titration. Ordinarily, apsirin is a weak acid and direct titration of aspirin is problematic because it hydrolyzes pretty fast to salicylic acid— leading to an unwanted side reaction which may or may not go to completion. Therefore, excess base must be added and heat is supplied to the mixture so that neutralization and hydrolysis are complete. The remaining base is then titrated. This is called back titration.
Now, in back titration, instead of using solution whose concentration is expected to be known, we rather use excess volume of reactant which has been left over after the completion of a reaction with the analyte.
In this case, we use an alkali, preferably NaOH (1.0 mol/dm³). Te unused NaOH remaining after the hydrolysis is titrated against a standard HCl (0.1 mol/dm³). Then from the reaction equation of the aspirin and sodium hydroxide, the amount of NaOH required for the hydrolysis can be calculated.
Answering whether the titration goes up or down, it would be observed that the titration reading would GO DOWN because the exposed aspirin used has experienced some form of hydrolysis before it was used for titration, so the hydrolysis reaction it would undergo with acetyl-salicylic acid would be minimal, and this would affect the titration reading.
But if the aspirin wasn't left exposed to the environment, the reading would go up since more hydrolysis would take place in this case.
273 Kelvin, 0 degrees Celsius, 32 degrees Fahrenheit
