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
Assoli18 [71]
3 years ago
9

What is the pH of a mixture of 0.042 M NaH2PO4 and 0.058 M Na2HPO4? Hint: The pKa of phosphate is 6.86.

Chemistry
1 answer:
AlekseyPX3 years ago
5 0

Answer:

The pH value of the mixture will be 7.00

Explanation:

Mono and disodium hydrogen phosphate mixture act as a buffer to maintain pH value around 7. Henderson–Hasselbalch equation is used to determine the pH value of a buffer mixture, which is mathematically expressed as,

pH=pK_{a} + log(\frac{[Base]}{[Acid]})

According to the given conditions, the equation will become as follow

pH=pK_{a} + log(\frac{[Na_{2}HPO_{4} ]}{[NaH_{2}PO_{4}]})

The base and acid are assigned by observing the pKa values of both the compounds; smaller value means more acidic. NaH₂PO₄ has a pKa value of 6.86, while Na₂HPO₄ has a pKa value of 12.32 (not given, but it's a constant). Another more easy way is to the count the acidic hydrogen in the molecular formula; the compound with more acidic hydrogens will be assigned acidic and vice versa.

Placing all the given data we obtain,

pH=6.86 + log(\frac{0.058}{0.042})

pH=7.00

You might be interested in
If the earth is about 13000 light years away from the outermost edge of the milky way galaxy, what is the total diameter of the
xeze [42]

Answer: The Milky Way is a barred spiral galaxy with a diameter between 150,000 and 200,000 light-years (ly).

3 0
3 years ago
What evidence supports a conservation law?
True [87]

Answer:

The answer is B.

Explanation:

The law of conservation of mass states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations.

According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants.

The law of conservation of mass is useful for a number of calculations and can be used to solve for unknown masses, such the amount of gas consumed or produced during a reaction.

3 0
3 years ago
Which solution has a molality of 0.25m nacl?
Solnce55 [7]

Molality can be expressed by moles of solute over kilograms of solvent. The question asks the molality of 0.25m NaCl. 0.25m NaCl is equal to 0.25 moles of NaCl over 1 kg of water.

5 0
3 years ago
Read 2 more answers
Can visible light cause damage that leads to skin cancer
11111nata11111 [884]

Visible and infrared light do not cause sunburn and they are not known to directly be a skin cancer risk.

7 0
2 years ago
The sink-float method is often used to identify the type of glass material found at crime scenes by determining its density.
Olegator [25]

Answer:

<em><u>Glass that will sink</u></em>

  • alkali zinc borosilicate with a density of 2.57 g/mL in a solution with a density of 2.46 g/mL

  • potash soda lead with a density of 3.05 g/mL in a solution with a density of 1.65 g/mL

<em><u>Glass that will float</u></em>

  • soda borosilicate with a density of 2.27 g/mL in a solution with a density of 2.62 g/mL

  • alkali strontium with a density of 2.26 g/mL in a solution with a density of 2.34 g/mL

<em><u>Glass that will not sink or float</u></em>

  • potash borosilicate with a density of 2.16 g/mL in a solution with a density of 2.16 g/mL

Explanation:

Density is the property of matter that states the ratio of the amount of matter, its mass, to the space occupied by it, its volume.

So, the mathematical expression for the density is:

  • density = mass / volume

By comparing the density of a material with the density of a liquid, you will be able to determine whether object will float, sink, or do neither when immersed in the liquid.

The greater the density of an object the more it will try to sink in the liquid.

As you must have experienced many times an inflatable ball (whose density is very low) will float in water, but a stone (whose denisty is greater) will sink in water.

The flotation condition may be summarized by:

  • When the density of the object < density of the liquid, the object will float
  • When the density of the object = density of the liquid: the object will neither float nor sink
  • When the density of the object > density of the liquid: the object will sink.

<em><u>Glass that will sink</u></em>

  • alkali zinc borosilicate with a density of 2.57 g/mL in a solution with a density of 2.46 g/mL, because 2.57 > 2.46.

  • potash soda lead with a density of 3.05 g/mL in a solution with a density of 1.65 g/mL, because 3.05 > 1.65.

<u><em>Glass that will float</em></u>

  • soda borosilicate with a density of 2.27 g/mL in a solution with a density of 2.62 g/mL, because 2.27 < 2.62.

  • alkali strontium with a density of 2.26 g/mL in a solution with a density of 2.34 g/mL, because 2.26 < 2.34.

<em><u>Glass that will not sink or float</u></em>

  • potash borosilicate with a density of 2.16 g/mL in a solution with a density of 2.16 g/mL, because 2.16 = 2.16
8 0
3 years ago
Other questions:
  • Define and give an example of an acid and of a base.
    7·1 answer
  • Aqueous carbonic acid H2CL3decomposes into carbon dioxide gas and liquid water . Write a balanced chemical equation for this rea
    15·2 answers
  • Which statement best describes a solution? A). a mixture consisting of minute particles suspended in a medium that start moving
    14·1 answer
  • Matter is anything that has mass. What is the smallest unit of matter known as?
    6·1 answer
  • What gas is produced when calcium metal is dropped in water
    6·1 answer
  • When 2-methyl-3-hexene is treated with Cl2 in methanol, three products are formed (neglecting stereoisomers). Draw curved arrows
    6·1 answer
  • Someone please help me real quick pls :(
    7·1 answer
  • Describe how the periodic
    9·1 answer
  • How many grams of NaOH are in 200 mL of a 3.OM NaOH<br> solution?<br> Na=23<br> O=16<br> H=1.01
    7·1 answer
  • Consider the balanced equation below.
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!