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
zysi [14]
3 years ago
8

An unknown salt is either NaF, NaCl, or NaOCl. When 0.050 mol of the salt is dissolved in water to form 0.500 L of solution, the

pH of the solution is 8.08. Part A What is the identity of the salt?
Chemistry
1 answer:
victus00 [196]3 years ago
6 0

<u>Answer:</u> The unknown salt is NaF

<u>Explanation:</u>

To calculate the molarity of solution, we use the equation:

\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}

Moles of salt = 0.050 moles

Volume of solution = 0.500 L

Putting values in above equation, we get:

\text{Molarity of salt}=\frac{0.050mol}{0.500L}\\\\\text{Molarity of salt}=0.1M

  • To calculate the hydroxide ion concentration, we first calculate pOH of the solution, which is:

pH + pOH = 14

We are given:

pH = 8.08

pOH=14-8.08=5.92

  • To calculate pOH of the solution, we use the equation:

pOH=-\log[OH^-]

Putting values in above equation, we get:

5.92=-\log[OH^-]

[OH^-]=10^{-5.92}=1.202\times 10^{-6}M

The unknown salt given are formed by the combination of weak acid and strong acid which is NaOH

The chemical equation for the hydrolysis of X^- ions follows:

                    X^-(aq.)+H_2O(l)\rightleftharpoons HX(aq.)+OH^-(aq.);K_b

<u>Initial:</u>              0.1

<u>At eqllm:</u>        0.1-x                           x              x

Concentration of OH^-=x=1.202\times 10^{-6}M

The expression of K_b for above equation follows:

K_b=\frac{[OH^-][HX]}{[X^-]}

Putting values in above expression, we get:

K_b=\frac{(1.202\times 10^{-6})\times (1.202\times 10^{-6})}{(1-(1.202\times 10^{-6}))}\\\\K_b=1.445\times 10^{-11}M

  • To calculate the acid dissociation constant for the given base dissociation constant, we use the equation:  

K_w=K_b\times K_a

where,

K_w = Ionic product of water = 10^{-14}

K_a = Acid dissociation constant

K_b = Base dissociation constant = 1.445\times 10^{-11}

Putting values in above equation, we get:

10^{-14}=1.445\times 10^{-11}\times K_a\\\\K_a=\frac{10^{-14}}{1.445\times 10^{-11}}=6.92\times 10^{-4}

We know that:

K_a\text{ for HF}=6.8\times 10^{-6}

K_a\text{ for HCl}=1.3\times 10^{6}

K_a\text{ for HClO}=3.0\times 10^{-8}

So, the calculated K_a is approximately equal to the K_a of HF

Hence, the unknown salt is NaF

You might be interested in
PLZ help Asap!!!!!! I WILL GIVE BRAINLIEST!!!
Sergeu [11.5K]

Answer: Chosen landforms are:

1) Hill

2) Mountain

3) Plateau

4) Valley

Explanation:

1) Hill is an elevated location smaller than a mountain. Location: Land

2) Mountain is a large mass of earth and rock, rising above the common level of the earth or adjacent land, usually given by geographers as above 1000 feet in height (or 304.8 metres).

Location: Land or Water

3) Plateau is a largely level expanse of land at a high elevation. It is also known as tableland.

Location: Land

4) Valley is an elongated depression between hills or mountains, often with a river flowing through it.

Location: Land or Water

6 0
3 years ago
Which of the following compounds are soluble in aqueous solutions? Select ALL that are soluble.
sattari [20]
<h3>Answer:</h3>
  • K₂S
  • CaSO₄ (slightly soluble in water)
  • Pb(ClO₄)₂
<h3>Explanation:</h3>
  • Mg(OH)₂  and CoCO₃ are insoluble in water.
  • Solubility rules are used to determine whether a compound will be soluble or not soluble in aqueous form.
  • K₂S is soluble in aqueous solutions as all salts of Potassium are soluble in water.
  • Calcium (ii) sulfate is slightly soluble in water.
  • Hydroxides are insoluble in water except, KOH, NaOH and NH₄OH.and Barium hydroxide. Therefore, Mg(OH)₂ is an insoluble hydroxide.
  • CoCO₃ is insoluble since carbonates are insoluble except K₂CO₃, Na₂CO₃ and (NH₄)₂CO₃. .
  • Pb(ClO₄)₂ is soluble because all perchlorates are soluble.
7 0
3 years ago
If Jerome is swinging on a rope and transferring energy from gravitational potential energy to kinetic energy, _____... is being
Pachacha [2.7K]

<u>Answer;</u>

-Work

If Jerome is swinging on a rope and transferring energy from gravitational potential energy to kinetic energy, <u>work </u> is being done.

<u>Explanation;</u>

  • Work refers to the application of a given force over a distance. Thus, we can say work is the product of force and distance.
  • Energy on the other hand is the ability of a body to change, its location, shape, or state of another body.
  • According to the work-Energy principle, a change in the kinetic energy, which is the energy possessed by a body in motion, is equivalent to the net work done on the body.
8 0
3 years ago
Read 2 more answers
what is the predicted order of fist ionization energies from highest to lowest for beryllium, calcium, magnesium, and stronium?
MrRa [10]
Lowest to highest:
Ca
Mg
Be
S
4 0
3 years ago
Read 2 more answers
Calculate the molarity of the solution formed when 0.72 moles of CaBr2 is dissolved in 1.50 L water.
xxTIMURxx [149]

Answer:

The molarity of the formed CaBr2 solution is 0.48 M

Explanation:

Step 1: Data given

Number of moles CaBr2 = 0.72 moles

Volume of water = 1.50 L

Step 2: Calculate the molarity of the solution

Molarity of CaBr2 solution = moles CaBr2 / volume water

Molarity of CaBr2 solution = 0.72 moles / 1.50 L

Molarity of CaBr2 solution = 0.48 mol / = 0.48 M

The molarity of the formed CaBr2 solution is 0.48 M

4 0
3 years ago
Other questions:
  • How many significant figures are in the quantity 12.0 mL?<br> O A. 1<br> B. 2<br> C. 3<br> O D. 12
    11·1 answer
  • State the relationship between electron configuration and location of an element in the period table
    10·1 answer
  • Draw it draw lewis dot structures for each hypothetical molecule shown below, using the correct number of valence electrons for
    9·1 answer
  • Two friends are arguing about the structure of the universe. Caleb says that the universe is made of many galaxies that are made
    11·1 answer
  • Which equation represents the total ionic equation for the reaction of HNO3 and NaOH?
    7·2 answers
  • The table below shows the shapes of two samples, C and D, when placed in three containers of different shapes. Shape of Sample S
    13·2 answers
  • At the beginning of the industrial revolution in 1850, the CO2concentration was 280 ppm. Today, it is 410 ppm.
    9·1 answer
  • What is the ratio of hydrogen atoms (H) to oxygen atoms (O) in 2 L of water? Enter the simplest whole number ratio in order of h
    7·1 answer
  • Essential amino acids cannot be made
    7·1 answer
  • Hi, in some texts number of water molecules released during polymerization is 2n but in others 2n-1 , why?
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!