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
slava [35]
3 years ago
8

How many grams of dry nh4cl need to be added to 2.50 l of a 0.800 m solution of ammonia, nh3, to prepare a buffer solution that

has a ph of 8.53? kb for ammonia is 1.8×10−5. express your answer with the appropriate units?
Chemistry
1 answer:
tia_tia [17]3 years ago
8 0

Answer:

The correct answer is 574.59 grams.

Explanation:

Based on the given information, the number of moles of NH₃ will be,  

= 2.50 L × 0.800 mol/L

= 2 mol

The given pH of a buffer is 8.53

pH + pOH = 14.00

pOH = 14.00 - pH

pOH = 14.00 - 8.53

pOH = 5.47

The Kb of ammonia given is 1.8 * 10^-5. Now pKb = -logKb,  

= -log (1.8 ×10⁻⁵)

= 5.00 - log 1.8

= 5.00 - 0.26

= 4.74

Based on Henderson equation:  

pOH = pKb + log ([salt]/[base])

pOH = pKb + [NH₄⁺]/[NH₃]

5.47 = 4.74 + log ([NH₄⁺]/[NH₃])

log([NH₄⁺]/[NH₃]) = 5.47-4.74 = 0.73

[NH₄⁺]/[NH₃] = 10^0.73= 5.37

[NH₄⁺ = 5.37 × 2 mol = 10.74 mol

Now the mass of dry ammonium chloride required is,  

mass of NH₄Cl = 10.74 mol × 53.5 g/mol

= 574.59 grams.  

You might be interested in
Which graphic below shows the correct orientation of each water molecule when it is near the cl- ion in the aqueous solution?
andrew-mc [135]
The question is missing the graphics required to answer which I have attached as an image.

There are four different representations of the orientation of water molecules around chloride anion. Let's first analyze the water molecule.

We have H-O-H as the structure of water. The oxygen atom is more electronegative than the hydrogen atoms, which results in a partial positive charge on the hydrogen atoms and a partial negative charge on the oxygen atom.

The chloride anion is a negative charge. Therefore, the water molecules should orient themselves with the hydrogen atoms facing the chlorine atom as the partial positive charge on the hydrogen atoms will be attracted to the negative charge of the chlorine atom.

The correct representation is shown in graph 3 which shows all hydrogen atoms facing the chlorine anion.

8 0
4 years ago
At equilibrium, no chemical reactions take place. true or false
arsen [322]
False. At equilibrium, the rate of forward reaction is equal to the rate of backward reaction. The net concentration of both products and reactants won't change, but the reactions still take place.
6 0
3 years ago
What is produced when a strong acid reacts with the bicarbonate buffer system in the human body?
Norma-Jean [14]
Carbonic acid is produced when a strong acid reacts with the bicarbonate buffer system in the human body.
7 0
3 years ago
Read 2 more answers
You place a carrot in salt water for 24 hours. what do you observe at the end of dat time? choose TWO CORRECT answer.
Xelga [282]

it will be shriviled due to the process called osmosis

5 0
3 years ago
Can you please help me to answer this? <br>I give you a brainlest! ​
zysi [14]
9 is B
6 is A
i’m not sure about the rest
5 0
3 years ago
Other questions:
  • According to the phase diagram for water, how is the state of water determined?
    13·2 answers
  • Two jars are placed on a counter with a McDonald's French Fry inside, one has a lid, the other does not. They are left alone to
    14·1 answer
  • Given the equation I2(s) + 62.4kJ --&gt; I2(g), which of the following is true:
    15·1 answer
  • Which model of acids and bases would NOT define NH3 as a base (even though it is considered one by the other models)?
    10·1 answer
  • Esterification is what type of reaction? 1.addition 2.neutralization 3.combustion 4.equilibrium
    11·2 answers
  • What is the total number of atoms in the formula<br> Ca(ClO3)2?
    11·2 answers
  • С
    13·1 answer
  • State one type of additional information that could be used to determine if these three species are closely related.
    10·1 answer
  • During an exothermic reaction, heat content in the surroundings increases because
    12·1 answer
  • Aryan want to deposit silver on an iron spoon using silver nitrate as electrolyte. Which terminal of the battery he should conne
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!