it 141 TR SH gu IS THE PIT IF LES UF SE 420 11 17 TE SE NE 1 NI HE NE 1 15 1 11 WI TE 1 ME UT 1 2 9 11 The + DEL RE 15
Posted: Tue May 17, 2022 3:55 pm
1-Which combinations of acid and base have the lower initial pH values? Are these the
expected results? Why?
2-For which acid-base combinations is the pH at the equivalent point neutral? Acidic?
Basic? Are these the expected results? Why?
3-A good indicator changes color in the vertical region of the titration curve.
Phenolphthalein changes from clear to red at a pH value of about 9. For which acid-
base combinations is pH=9 on the vertical region? For which acid-base combinations
does the time of the indicator color change and the time at the equivalence point
agree? Are these two lists the same?
it 141 TR SH gu IS THE PIT IF LES UF SE 420 11 17 TE SE NE 1 NI HE NE 1 15 1 11 WI TE 1 ME UT 1 2 9 11 The +
DEL RE 151 ME RE HEL NE TE 4 IT TIE * EN 21 17 HT 1 13 NE 11 BT NE NE 11 OHHON WE TE M RESULTS: I VES OF STRONG AND WEAK ACIDS AND BASES
Table 1 - Equivalence Point and Indicator Color Change - Acid-Base Combination Initial pH Final pH Time of Indicator Color Change (sec) Time at Equivalence Point (sec) 88.5 80.5 pH at the Equivalence Point 7.5 87 HCl + NaOH HC2H302 + NaOHT HCI + NH OH WH HC2H302 + NH4OH 8.5 83 73 254 1663 3.72 1.3 2.10 1.77 611 119 53 دک 9
expected results? Why?
2-For which acid-base combinations is the pH at the equivalent point neutral? Acidic?
Basic? Are these the expected results? Why?
3-A good indicator changes color in the vertical region of the titration curve.
Phenolphthalein changes from clear to red at a pH value of about 9. For which acid-
base combinations is pH=9 on the vertical region? For which acid-base combinations
does the time of the indicator color change and the time at the equivalence point
agree? Are these two lists the same?
it 141 TR SH gu IS THE PIT IF LES UF SE 420 11 17 TE SE NE 1 NI HE NE 1 15 1 11 WI TE 1 ME UT 1 2 9 11 The +
DEL RE 151 ME RE HEL NE TE 4 IT TIE * EN 21 17 HT 1 13 NE 11 BT NE NE 11 OHHON WE TE M RESULTS: I VES OF STRONG AND WEAK ACIDS AND BASES
Table 1 - Equivalence Point and Indicator Color Change - Acid-Base Combination Initial pH Final pH Time of Indicator Color Change (sec) Time at Equivalence Point (sec) 88.5 80.5 pH at the Equivalence Point 7.5 87 HCl + NaOH HC2H302 + NaOHT HCI + NH OH WH HC2H302 + NH4OH 8.5 83 73 254 1663 3.72 1.3 2.10 1.77 611 119 53 دک 9