chemistry help please!! something to do with neutralization??

Question

A 1.1058g sample of seashell was reacted with 25.00 ml of 1.000M HCl. The excess HCl required 21.70 ml of 0.1590M NaOH for neutralization.

1. Why are the eggshells dried before they are massed?

2. Why are the eggshells crushed before they are used in the reaction?

3. As the mass of the eggshell sample increases, what will happen to the volume of NaOH solution required for the titration? Explain.


if you have any idea what the answer is, pleaseee help me! thanks!

Answer 1

Your problem says "a 1.1058 gm. sample of seashell", but
the 3 questions all ask about egg shells. Fortunately, they
are the same thing chemically, calcium carbonate.
1. You dry the shell to remove excess water, which will make
the sample appear to weigh more than it actually does
2. The shells are crushed to make them react faster with the
dilute acid so you don't take all day waiting for it to react.
3. As the mass of the sample increases, it will use up more
of the acid reacting, which leaves less unreacted acid to
be neutralized by the sodium hydroxide. Therefore, less
sodium hydroxide solution will be required to neutralize
the reduced amount of excess acid.

Answer 2

This is called a "reverse titration" Th egg shell contains CaCO3 and this is reacting with the HCl. There is left over HCL and this is then neutralized with NaOH. By knowing how much NaOH you needed, you can calculate how much extra HCl there was. Subtract this from the original amount and you can calculate how much HCl reacted with the egg shell. Once you know that, you can use stoichiometry to calculate how much CaCO3 you had.

The egg shells are dried and crushed to make the reaction clean and fast.

If you have more egggshell, do you think you would need more or less HCl? If you used more HCl, would there be more or less HCl left over at the end? If there was less left over at the end, would you need more or less NaOH to neutralize the excess?

Answer 3

1. If you don't dry the eggshells before weighing them, then you're weighing eggshells and water, not just eggshells. But how did we get from seashells to eggshells, anyway?

2. Eggs are waxed before they are sold to consumers. Crushing the eggshells makes the eggshell available for chemical reaction.

3. Less caustic soda will be required for neutralization, as a greater amount of eggshell means more hydrochloric acid will be used up reacting with the shells.

Answer 4

no longer precisely suited yet you have have been given the superb theory. A neutralization reaction takes place "between" an acid and a base, no longer with water and the acid and base. Its called neutralization using fact after the reaction, a salt and water is shaped, no acids or bases. So we could take a seem KOH (aq) + HCl (aq) --> Potassium hydroxide is the backside and Hydrochloric acid is the acid. They replace their anions (OH- and Cl-) and cations (ok+ and H+). This produces water and potassium chloride, a salt. KOH (aq) + HCl (aq) --> KCl (aq) + H2O (l) After this ruin it down into the internet ionic. ok+(aq) + OH-(aq) + H+(aq) + Cl-(aq) --> ok+(aq) + Cl-(aq) + H2O(l) H2O does not ruin down into its ions using fact its in its liquid form. each thing cancels to grant H+(aq) + OH-(aq) --> H2O (l) it rather is what the internet ionic equation of a neutralization reaction could appear as if. The spectator ions is each thing that cancels out, it rather is ok+(aq) and Cl-(aq) subsequently. wish this helps.