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
alekssr [168]
3 years ago
8

Ca(OH)2 (s) precipitates when a 1.0 g sample of CaC2(s) is added to 1.0 L of distilled water at room temperature. If a 0.064 g s

ample of CaC2 (s) (molar mass 64 g/mol) is used instead and all of it reacts, which of the following will occur and why?
(the value of Ksp for Ca(OH)2 is 8.0 x 10-8)

(A)Ca(OH)2 will precipitate because Q >K sp.

(B)Ca(OH)2will precipitate because Q
(C)Ca(OH)2 will not precipitate because Q >K sp .

(D)Ca(OH)2 will not precipitate because Q
Chemistry
1 answer:
Nina [5.8K]3 years ago
8 0

Answer:

D) Ca(OH)₂ will not precipitate because Q <  Ksp

Explanation:

Here we have first a chemical reaction in which Ca(OH)₂  is produced:

CaC₂(s)  + H₂O ⇒ Ca(OH)₂ + C₂H₂

Ca(OH)₂  is slightly soluble, and depending on its concentration it may precipitate out of solution.

The solubility product  constant for Ca(OH)₂  is:

Ca(OH)₂(s) ⇆ Ca²⁺(aq) + 2OH⁻(aq)

Ksp = [Ca²⁺][OH⁻]²

and the reaction quotient Q:

Q = [Ca²⁺][OH⁻]²

So by comparing Q with Ksp we will be able to determine if a precipitate will form.

From the stoichiometry of the reaction we know the number of moles of hydroxide produced, and since the volume is 1 L the molarity will also be known.

mol Ca(OH)₂ = mol CaC₂( reacted = 0.064 g / 64 g/mol = 0.001 mol Ca(OH)₂

the concentration of ions will be:

[Ca²⁺ ] = 0.001 mol / L 0.001 M

[OH⁻] = 2 x 0.001 M  = 0.002 M  ( From the coefficient 2 in the equilibrium)

Now we can calculate the reaction quotient.

Q=  [Ca²⁺][OH⁻]² = 0.001 x (0.002)² = 4.0 x 10⁻⁹

Q < Ksp since 4.0 x 10⁻⁹ < 8.0 x 10⁻⁸

Therefore no precipitate will form.

The answer that matches is option D

You might be interested in
There are<br><br> molecules of carbon dioxide (CO2) in 102.5 grams.
Gekata [30.6K]

Answer:

1.403x10²⁴ molecules

Explanation:

In order to calculate how many molecules of CO₂ are there in 102.5 g of the compound, we first<u> convert grams to moles</u> using its <em>molar mass</em>:

  • 102.5 g ÷ 44 g/mol = 2.330 mol CO₂

Now we <u>convert moles into molecules </u>using <em>Avogadro's number</em>:

  • 2.330 mol * 6.023x10²³ molecules/mol = 1.403x10²⁴ molecules
7 0
2 years ago
The following properties are either physical or chemical. Which one is different from the rest based on those two categories? (5
Yuliya22 [10]

Answer:

The following properties are either physical or chemical. Which one is different from the rest based on those two categories? We chose all of the above

4 0
3 years ago
Jeremy bought a new truck for $32,000. The value of the truck after t years can be represented by the formula V = 32,000(.8)t. H
Irina18 [472]

Your answer is  $20,480.

Hope this Helped!

<h3>Also here is the explanation: </h3><h3>https://www.symbolab.com/solver/equation-calculator/x%3D32000%5Cleft(.8%5Cright)%5E%7B2%7D</h3>
7 0
3 years ago
For the following reaction, 7.72 grams of nitrogen gas are allowed to react with 4.86 grams of oxygen gas . nitrogen(g) oxygen(g
inn [45]
There could be a big maximum amount or small, either works
7 0
3 years ago
baseball fields have dirt in the infield and grass in the outfield. the is more likely to erode because
eimsori [14]
Grass is more likely to erode.
3 0
3 years ago
Other questions:
  • Because the light rays never meet, a concave lens can produce
    6·1 answer
  • A rechargeable battery initially stores 3.6 kJ of chemical energy. Anna puts the battery in a flashlight, where 2.1 kJ of energy
    8·1 answer
  • What would be the resulting molarity of a solution made by dissolving 45.7 grams of Mg(OH)2 in enough water to make a 1087-milli
    15·2 answers
  • The isotope 3115p is also called ___________
    9·1 answer
  • To vaporize/condense a substance, does the substance have to absorb or release heat?
    12·1 answer
  • Reasons Sharecropping Developed<br> Which of the following were reasons why sharecropping developed?
    7·1 answer
  • The alchemists were the first to do what?
    10·1 answer
  • A 10.00 mL sample of a 1.07 M solution of potassium hydrogen phthalate (KHP, formula mass = 204.22 g/mol) is diluted to 250.0 mL
    7·1 answer
  • Hi can someone please help me!
    8·1 answer
  • Hello people ~
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!