It is rinsed one last time with the solution to be measured because if there is water in the burret, then it could alter the results. Slightly, but it is still altering it.
Answer:
<em>D. One negative charge</em>
Explanation:
During the formation of a bond, if an atom gains an electron, after that it will be left with a negative charge compared to the atom before the bond is formed. This is because in these types of bonds, which are <em>ionic bonds</em>, there is a <em>transfer of electrons between atoms</em>, there will be one or more atoms that yield electrons that will be captured by another and other atoms that gain them, and the difference of charges produced by this transfer of electrons, will cause the union to occur due to the attraction between electrostatic forces.
If you have a neutral atom before joining, and it gains an electron to form a bond,<em> it will have one electron more than its initial state</em> (in the initial state, the number of protons and electrons is the same, because the atoms they are electrically neutral), so having an extra electron will make it have a negative charge, since there will be a difference between the number of protons and electrons that the atom possesses. <em>This is why the correct answer is D.
</em>
In the case of <em>response A and B</em>, <em>the atom could only remain positively charged if it loses electrons</em>, but as in this case it wins, <em>they are not correct</em>.
<em>The answer C is also not correct</em> because only one electron wins, so that it is left with two negative charges, <em>it should gain two electrons during the bond formation.</em>
Answer:
- <u>Yes,</u> <em>all titrations of a strong base with a strong acid have the same pH at the equivalence point.</em>
This <u>pH is 7.</u>
Explanation:
<em>Strong acids</em> and <em>strong bases</em> ionize completely in aqueous solutions. The ionization of strong acids produce hydronium ions, H₃O⁺, and the ionization of strong bases produce hydroxide ions, OH⁻.
Since the ionization of strong acids and bases progress until completion, there is not reverse reaction.
The definition of pH is pH = - log [H₃O⁺]. Acids have low pH (below 7, and greater than 0) and bases have high pH (above 7 and less than 14). Neutral solutions have pH = 7.
Acid-base titrations are a method to determine the concentration of an acid from the known concentration of a base, or the concentraion of a base from the known concentration of an acid.
The<em> equivalence point</em> of the titration is the point at which the the number of moles of hydronium ions and hydroxide ions are equal.
Then, at that point, the hydronium and hydroxide ions will be in the stoichiometric proportion to form a neutral solution, i.e. the pH of the solution wiill be 7.
A should be the products and D should be the reactants. So D should be the answer.