1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
MAVERICK [17]
4 years ago
15

In this experiment, you used phenolphthalein to monitor the neutralization reactions. describe the chemical differences between

an equivalence point and an endpoint in titration and use this to explain whether phenolphthalein could be used as an indicator in any acid/base neutralization.
Chemistry
1 answer:
viva [34]4 years ago
6 0
The endpoint in tiration is the point where an indicatior's halfway thru its color change. Equivalence point is where moles/stoichiometry of the system is satisfied (moles of reactants are equal to each other).

Titrating a strong acid with a strong base results in a salt that is neutral. Phenolphthalein changes color in the range <span>8.3 – 10. It is very easy to spot the change as it is colorless in acidic (< 8.3) and pink in basic (> 10).

pH will rapidly change near titration equivalence point. </span><span>Only one drop of the titrant causes this large change, the color change of phenolphthalein does not occur on the equivalence point, but IT IS within about 1 drop. <span>It would be considered an "acceptable uncertainty" in using titration to determine concentration by volumetric measurement.</span></span>

You might be interested in
A student is asked to standardize a solution of potassium hydroxide. He weighs out 1.08 g potassium hydrogen phthalate (KHC8H4O4
natka813 [3]

Answer:

A. 0.143 M

B. 0.0523 M

Explanation:

A.

Let's consider the neutralization reaction between potassium hydroxide and potassium hydrogen phthalate (KHP).

KOH + KHC₈H₄O₄ → H₂O + K₂C₈H₄O₄

The molar mass of KHP is 204.22 g/mol. The moles corresponding to 1.08 g are:

1.08 g × (1 mol/204.22 g) = 5.28 × 10⁻³ mol

The molar ratio of KOH to KHC₈H₄O₄ is 1:1. The reacting moles of KOH are 5.28 × 10⁻³ moles.

5.28 × 10⁻³ moles of KOH occupy a volume of 36.8 mL. The molarity of the KOH solution is:

M = 5.28 × 10⁻³ mol / 0.0368 L = 0.143 M

B.

Let's consider the neutralization of potassium hydroxide and perchloric acid.

KOH + HClO₄ → KClO₄ + H₂O

When the molar ratio of acid (A) to base (B) is 1:1, we can use the following expression.

M_{A} \times V_{A} = M_{B} \times V_{B}\\M_{A} = \frac{M_{B} \times V_{B}}{V_{A}} \\M_{A} = \frac{0.143 M \times 10.1mL}{27.6mL}\\M_{A} =0.0523 M

8 0
3 years ago
The Chandrasekhar limit states that the final mass of a _____ star can be no greater than 1.4 solar masses.
Marrrta [24]
Stable white dwarf star
6 0
3 years ago
Read 2 more answers
How can you overcome drawback of a chemaicl equation ? any three​
Shtirlitz [24]

Answer:

1.rate of reaction should be indicated by symbols 2.we should indicate physical states by sybloms 3.reversible reaction should be indicated by using double arrows

4 0
3 years ago
Mixtures have no unique physical properties.<br> true or false
umka21 [38]
The answer is false
8 0
4 years ago
Sodium hydride reacts with excess water to produce aqueous sodium hydroxide and hydrogen gas:NaH (s) H2O (l) → NaOH (aq) H2 (g)A
Anuta_ua [19.1K]

NaH(s)+ H2O (l)=>NaOH(aq)+H2(g)

You want to calculate the mass of NaH, I assume.  Otherwise, the question isn't clear.  It simply says calculate the mass(??)

 

So, calculate the moles of H2 gas that satisfy the conditions of 982 ml at 28ºC and 765 torr.  But you must subtract the vapor pressure of water at 28º to get the actual pressure of the H2 gas.  So, the actual conditions are 982 ml (0.982 L) and 301 K and 765-28 = 737 torr.

PV = nRT

n = PV/RT = (737 torr)(0.982 L)/(62.4 L-torr/Kmol)(301 K)

n = 0.0385 moles H2

 

moles NaH needed = 0.0385 moles H2 x 1 mole NaH/mole H2 = 0.0385 moles NaH required

mass of NaH needed = 0.0385 moles x 24 g/mole = 0.925 g NaH

Brainliest Please :)

7 0
4 years ago
Read 2 more answers
Other questions:
  • Which is bigger 108kg vs 10800g
    12·1 answer
  • Molarity of 2%W/V of NaOH is
    12·1 answer
  • A molecule, that is sp3d2 hybridized and has a molecular geometry of square pyramidal, has ________ bonding groups and ________
    12·1 answer
  • Part A
    5·1 answer
  • 30)
    12·2 answers
  • When iron rusts in air, iron(III) oxide is produced.
    12·1 answer
  • Which one is used in magnets often nickle or lead?
    7·1 answer
  • Calcium hydroxide, Ca(OH)2, is an ionic compound with a solubility product constant, Ksp, of 6.5×10–6. Calculate the solubility
    15·1 answer
  • An object has a mass of 300g <br>a. what is it mass on Earth <br>b. what is it's mass on the moon​
    6·1 answer
  • What type of nonvisible light has a longer wavelength than the color red?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!