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
Ahat [919]
3 years ago
10

HC]A laboratory experiment requires 2.0 L of a 1.5 M solution of hydrochloric acid (HCl), but the only available HCl is a 12.0 M

stock solution. How could you prepare the solution needed for the lab experiment? Show all the work used to find your answer
Chemistry
1 answer:
andreyandreev [35.5K]3 years ago
3 0

The amount of the solute is constant during dilution. So the mole number of HCl is 2*1.5=3 mole. The volume of HCl stock is 3/12=0.25 L. So using 0.25 L stock solution and dilute to 2.0 L.

You might be interested in
At a certain temperature the equilibrium constant, Kc, equals 0.11 for the reaction:
Butoxors [25]

<u>Answer:</u> The equilibrium concentration of ICl is 0.27 M

<u>Explanation:</u>

We are given:

Initial moles of iodine gas = 0.45 moles

Initial moles of chlorine gas = 0.45 moles

Volume of the flask = 2.0 L

The molarity is calculated by using the equation:

\text{Molarity}=\frac{\text{Number of moles}}{\text{Volume}}

Initial concentration of iodine gas = \frac{0.45}{2}=0.225M

Initial concentration of chlorine gas = \frac{0.45}{2}=0.225M

For the given chemical equation:

2ICl(g)\rightarrow I_2(g)+Cl_2(g);K_c=0.11

As, the initial moles of iodine and chlorine are given. So, the reaction will proceed backwards.

The chemical equation becomes:

                      I_2(g)+Cl_2(g)\rightarrow 2ICl(g);K_c=\frac{1}{0.11}=9.091

<u>Initial:</u>         0.225      0.225

<u>At eqllm:</u>   0.225-x    0.225-x     2x

The expression of K_c for above equation follows:

K_c=\frac{[ICl]^2}{[Cl_2][I_2]}

Putting values in above equation, we get:

9.091=\frac{(2x)^2}{(0.225-x)\times (0.225-x)}\\\\x=0.135,0.668

Neglecting the value of x = 0.668 because equilibrium concentration cannot be greater than the initial concentration

So, equilibrium concentration of ICl = 2x = (2 × 0.135) = 0.27 M

Hence, the equilibrium concentration of ICl is 0.27 M

6 0
3 years ago
Police investigating the scene of a sexual assault recover a large blanket that they believe may contain useful physical evidenc
goldfiish [28.3K]

Answer:

Acid Phosphatase (AP) Test

Explanation:

Acid phosphate is an enzyme that is found in the body. It is secreted majorly by the prostrate gland into the seminal fluid. The acid phosphatase test is used to test for the presence of semen in items.

Scott chose the acid phosphatase test because it is very useful in testing for semen on large items such as blankets. The reaction time for an acid phosphatase test for semen is less than 30 seconds. Seeing that the test was completed in three minutes, Scott concluded that the positive reaction was as a result of some other fluid.

The detectives reported that an overturned bowl of grapes and watermelon was found at the scene as well as a broken glass that had contained wine. Scott knew that some fruit juices like that of watermelon give a positive reaction to the acid phosphatase test but with  more time that of the semen fluid because the reaction is a very slow one.

Scott concluded that there was no presence of semen on the blanket and therefore there was no sexual assault.

4 0
3 years ago
[H3O+] [OH−] pH Acidic or Basic 3.5×10−3 _____ _____ _____ _____ 3.8×10−7 _____ _____ 1.8×10−9 _____ _____ _____ _____ _____ 7.1
ankoles [38]

Answer:

See explanation below

Explanation:

I'm assuming this is a table you need to complete, so, you are not putting this in order, but I already found it in another place. let's do a little summary of the expressions we need to use in order to complete the chart.

To calculate pH we need the following expression:

<em>pH = -log[H3O+] (1)</em>

From this expression we can solve for [H3O+] in case we need it:

<em>[H3O+] = 10^(-pH)   (2)</em>

When we have [OH-] we calculate the pOH and from there, the pH:

<em>pOH = -log[OH-]  (3)</em>

and [OH-]:

<em>[OH-] = 10^(-pOH) (4)</em>

Finally to get the pH from pOH:

14 = pH + pOH

<em>pH = 14 - pOH (5)</em>

With these 5 expressions we can complete the chart. In picture 1, you have the actual chart.

To know if it's acidic or basic, that depends on the value of pH.

If pH <7 it's acidic

If pH >7 it's basic

If pH = 7 it's neutral

<u><em>First case:</em></u>

[H3O+] = 3.5x10^-3

pH = -log(3.5x10^-3) = 2.46  (acidic)

pOH = 14 - 2.46 = 11.54

[OH-] = 10^(-11.54) = 2.88x10^-12 M

<u><em>Second case:</em></u>

pOH = -log(3.8x10^-7) = 6.42

pH = 14 - 6.42 = 7.58 (it's basic)

[H3O+] = 10^(-7.58) = 2.63x10^-8 M

<u><em>Third case:</em></u>

pH = -log(1.8x10^-9) = 8.74 (it's basic)

pOH = 14 - 8.74 = 5.26

[OH-] = 10^(-5.26) = 5.5x10^-6 M

<u><em>Fourth case:</em></u>

[H3O+] = 10^(-7.15) =7.08x10^-8 M   (Basic)

pOH = 14 - 7.15 = 6.85

[OH-] = 10^(-6.85) = 1.41x10^-7 M

Hope this can help you

7 0
3 years ago
4. What is the dependent variable in the statement below?
Naddik [55]
A. Amount of sleep, since it depends on how much coffee she drinks
4 0
4 years ago
Read 2 more answers
1) Rank the elements, aluminum, sodium and phosphorus, in order of decreasing conductivity.
miss Akunina [59]

Conductivity is the ability of a substance to allow charge or electricity to pass through it. Metals have a lot of free electrons and are considered as good conductors while non-metals do not conduct electricity

1) In the given examples:

Al is a metal, Na is an alkali metal while P is a non-metal

The decreasing order of conductivity would be:

Al > Na > P

2)

Both Al and Ga are metals while B is metalloid.

Among Al and Ga, Al is a solid at room temperature and a better conductor of electricity. hence the decreasing order would be:

Al > Ga > B

8 0
4 years ago
Other questions:
  • Name an element in the fourth period (row) of the periodic table with three 3d electrons.
    15·1 answer
  • Determine the correct Lewis structure for ammonia (NH3). Note: Hydrogen and nitrogen have one and five valence electrons respect
    12·1 answer
  • Unlike the nervous system, the endocrine system ___ A) Responds quickly B) Does not respond C) Rarely responds D) Responds Slowl
    10·1 answer
  • How can you tell from the name the types of bonds present in a hydrocarbon?
    15·1 answer
  • Which statement correctly compares the number of chromosomes in a body cell to that in a sex cell of humans?
    6·2 answers
  • using the knowledge of the structures of argon and chlorine. Explain why they are both gases at room temperature ?
    7·1 answer
  • Explain how energy is transferred in a food web.
    6·2 answers
  • What is the difference between endothermic and exothermic reaction (shortest answer)
    10·2 answers
  • Which disease is caused by a living pathogen? a. common colds b. smallpox c. cholera d. influenza
    11·1 answer
  • Which isoelectronic series is correctly arranged in order of increasing radius?.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!