AP Chem 2 chapter 4
Conjugate base
An element that gains a hydrogen from a Brønsted-Lowry acid
Conjugate acid
An element that looses a hydrogen from its original Bronsted-Lowry pair
Na2CO3(aq) + 2HCl -> 2NaCl(aq) + H2)l)+CO2(g) What experimental result would be evidence that a chemical reaction took place when the solutions were combined?
Bubbles formed when the two solutions were combined
A beaker was half filled with freshly distilled H2O and placed on a hot plate. As the temperature of the water reached 100 degrees C, vigorous bubbling was observed in the beaker. The gaseous contents of the bubbles were analyzed. The presence of which of the following substances would support the claim that the observed phenomenon was a physical change?
H2O
Based on the Bronsted-Lowry theory of acids and bases, which of the following species can act as both a conjugate acid and a conjugate base?
HS-
NH3 + H2O --> NH4+ + OH- Which of the following best describes the process represented above that takes place when NH3 is added to water?
It is an acid-base reaction in which a proton is exchanged from H2O to NH3. (N is gaining a hydrogen, making it act like a base. the H2O is acting like an acid because it looses a hydrogen)
2 Mg(s) + SiCl4 -> 2 MgCl2(2) + Si(s) Which of the Following statements about the reaction represented above is correct?
It is an oxidation-reduction reaction and Mg is oxidized
Zn(s) + 2HCl(aq) -> ZnCl2(aq) + H2(g) When the reaction represented above proceeds, heat is produced. Which of teh following best describes the reaction?
It is an oxidation-reduction reaction because zinc is oxidized and hydrogen is reduced
HC2H3O2(aq) + OH-(aq) -> C2H3O2-(aq) + H2O(l) A student carried out a titration using HC2H3O2(aq). The net ionic equation reaction that occurred during the titration is represented above. The NaOH(aq) was added from a burst to the HC2H3O2(aq) in a flask. The equivalence point was reached when a total of 20.0 mL of NaOH(aq) had been added to the flask. How does the amount of HC2H3O2(aq) in the flask after the addition of 5.0mL of NaOH(aq) compare to the amount of HC2H3O2(aq) in the flask after the addition of 1.0mL of NaOH(aq), and what is the reason for this result?
It is less because more HC2H3O2(aq) reacted with the base (20 mL of NaOH is needed to completely neutralize. It hasnt reached the equivalence point yet.)
A student combines a solution of NaCl(aq) with a solution of AgNO3(aq), and a precipitate forms. Assume that 50.0mL of 1.0 M NaCl(aq) and 50.0mL of 1.0 M AgNO3 (aq) were combined. According to the balanced equation, if 50.0 mL of 2.0 M NaCl(aq) and 50.0mL of 1.0 M AgNO3 were combined, the amount of precipitate formed would
Not change, because the amount of AgNO3 did not change (you would need to double the AgNO3 aswell to double the product)
Which of the following is the correct net ionic equation of the neutralization reaction between hydrofluoric acid and sodium hydroxide in an aqueous solution?
The one with H2O and F- as the products
A student combines a solution of NaCl(aq) with a solution of AgNO3(aq), and a precipitate forms. Which of the following is evidence that ionic bonds formed during the precipitation?
The precipitate has a high melting point.
