Answer:
Take approx 41.7 mL of 12-M HCl in a 1.00-L flask and fill the rest of the volume with distilled water.
Explanation:
Hello,
In this case, for the dilution process from concentrated 12-M hydrochloric acid to 1.00 L of the diluted 0.50M hydrochloric acid, the volume of concentrated HCl you must take is computed by considering that the moles remain constant for all dilution processes as shown below:
[tex]n_1=n_2[/tex]
Which can also be written in terms of concentrations and volumes:
[tex]M_1V_1=M_2V_2[/tex]
Thus, solving for the initial volume or aliquot that must be taken from the 12-M HCl, we obtain:
[tex]V_1=\frac{M_2V_2}{M_1} \\\\V_1=\frac{1.00L*0.5M}{12M}\\ \\V_1=0.0417L=41.7mL[/tex]
It means that you must take approx 41.7 mL of 12-M HCl in a 1.00-L flask and fill the rest of the volume with distilled water for such preparation.
Best regards.
Which of these tasks falls under the responsibility of a forensic scientist?
Cleaning the crime scene after evidence has been collected
Determining whether or not a suspect is guilty of the crime
Examining and signing petitions for search warrants
Training officers in how to properly collect evidence
Answer:
Training officers in how to properly collect evidence
Explanation:
Forensic science is an interesting branch of science that involves the use of scientific procedures to solve a crime case. It encompasses collection of physical evidence from the crime scene and analyzing it in a laboratory using scientific means.
A forensic scientist is the individual in charge of performing these scientific procedures. His/her major role is to run the scientific analysis of the physical evidence brought in by the officers, however, he/she can also perform the task of training officers in how to properly collect evidence, in order not to damage the evidence or render it invalid for use.
The density of pure silver is 10.5 g/cm3 at 20°C. If 5.25 g of pure silver pellets is added to a graduated cylinder containing 16.1 mL of water, to what volume level will the water in the cylinder rise?
Answer:
The correct answer is 16.6 mL
Explanation:
The density of a substance is defined as its mass per unit of volume. Thus:
density = mass/volume
So, to calculate volume: volume = mass/density
Given:
density= 10.5 g/cm³
mass= 5.25 g
We calculate the volume occupied by silver as follows:
volume= mass/density= (5.25 g)/(10.5 g/cm³)= 0.5 cm³
Moreover, we know that 1 cm³= 1 ml. So, a mass of 5.25 g of pure silver occupies a volume of 0.5 ml. If we add the mass of silver to a graduated cylinder with 16.1 mL of water, the final volume will be given by the initial volume of water plus the volume occupied by silver:
volume level = 16.1 mL + 0.5 mL = 16.6 mL
The density of the pure silver substance is defined as the mass per volume. The water level of the cylinder will rise to 16.6 mL after silver pellets are added to the cylinder.
What is density?The density of the silver metal can be explained by the division of the mass of the silver pellets by the volume of the water in the cylinder. The density has been seen in inverse relation to the volume and has been decreasing with an increase in volume.
Similarly, if the volume of the solution is decreased then the density of the substance will increase. As D ∝ 1 /V.
The density of the substance is given as:
Density (D) = mass ÷ volume
Given,
Density (D) = 10.5 g/cm³
Temperature = 20°C
Mass of silver pellets = 5.25 grams
The volume of water in the graduated cylinder = 16.1 mL
The volume of the silver is calculated as:
Volume = mass ÷ density
V = 5.25 g ÷ 10.5 g/cm³
= 0.5 cm³
= 0.5 mL (1 cm³ = 1 mL)
The volume level is calculated by adding the volume of silver and water as: 16.1 mL + 0.5 mL = 16.6 mL
Therefore, 16.6 mL is the volume.
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In which pair would both compounds have the same empirical formula?
a. FeO and Fe2O3
b. H2O and H2O2
c. C6H12O6 and HC2H3O2
d. BaSO4 and BaSO3
You need to prepare an acetate buffer of pH 5.36 from a 0.900 M acetic acid solution and a 2.62 M KOH solution. If you have 680 mL of the acetic acid solution, how many milliliters of the KOH solution do you need to add to make a bufer of pH 5.93? The pKa of acetic acid is 4.76.
Answer:
Explanation:
pH = pKa + log [ CH₃COO⁻ ] / [CH₃COOH ]
5.36 = 4.86 + log [ CH₃COO⁻ ] / [CH₃COOH ]
log [ CH₃COO⁻ ] / [CH₃COOH ] = .5
[ CH₃COO⁻ ] / [CH₃COOH ] = 3.16
moles of CH₃COOH = .680 x .9 = .612 M
Let x mole of KOH is required
x /( .612 - x ) = 3.16
x = 1.933 - 3.16 x
x = .46488
.46488 moles of KOH will be required
volume required be V
v x 2.62 = .46488
v = .1774 L
= 177.4 mL
177.4 mL of 2.62 M KOH will be required .
The number of milliliters of the KOH solution is 177.4 mL
Calculation of the number of milliliters of the KOH solution:Since we know that
H = pKa + log [ CH₃COO⁻ ] / [CH₃COOH ]
5.36 = 4.86 + log [ CH₃COO⁻ ] / [CH₃COOH ]
Now
log [ CH₃COO⁻ ] / [CH₃COOH ] = .5
[ CH₃COO⁻ ] / [CH₃COOH ] = 3.16
Therefore,
moles of CH₃COOH = .680 x .9 = .612 M
here we assume x mole of KOH
So,
x /( .612 - x ) = 3.16
x = 1.933 - 3.16 x
x = .46488
Now the volume required is
v x 2.62 = .46488
v = .1774 L
= 177.4 mL
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Consider the following expression:8.30 x 10^-5 = x(0.100 + x)^2We can solve for x using a technique called successive approximations.8.30 x 10^-5 =x1 (0.100)^2Step 1: If we assume that x is very small compared to 0.100 (such that 0.100 x ? 0.100) then our first approximation of x (let\'s call it x1) can be calculated asx1 = ?Step 2: Now, take your first approximation of x and plug it into the full equation.8.30 x 10^-5 =x2 (0.100 + x1)^2x2 = ?Step 3: Each successive approximation uses the value from the previous approximation.8.30 x 10^-5 =x3 (0.100 +x2)^2x3 = ?Step 4, etc.: Continue this process until two x values agree within the desired level of precision.x4 = ?x5 = ?Which values are the first to agree to two significant figures?a. x1 and x2b. x2 and x3c. x3 and x4d. x4 and x5Which values are the first to agree to three significant figures?a. x1 and x2b. x2 and x3c. x3 and x4d. x4 and x5
Answer:
a. x3 and x4 are the first to agree to two significant figures
b. x4 and x5 are the first to agree to three significant figures
Explanation:
8.30 x 10⁻⁵ = x1(0.100)²
8.30 x 10⁻⁵ = 0.01x1
x1 = 8.30 x 10⁻⁵/0.01 = 0.0083
8.30 x 10⁻⁵ = x2(0.100 + 0.0083)²
8.30 x 10⁻⁵ = (0.01172889)x2
x2 = 8.30 x 10⁻⁵/0.01172889
x2 = 0.007076543475128
8.30 x 10⁻⁵= x3 (0.100 + 0.007076543475128)²
8.30 x 10⁻⁵ = 0.011465386162581)x3
x3 = 8.30 x 10⁻⁵/0.011465386162581
x3 = 0.007239180505832
8.30 x 10⁻⁵ = x4 (0.100 + 0.007239180505832)²
8.30 x 10⁻⁵ = (0.011500241835562) x4
x4 = 8.30 x 10⁻⁵/0.011500241835562
x4 = 0.007217239531723
8.30 x 10⁻⁵ = x5 (0.1 + 0.007217239531723)²
8.30 x 10⁻⁵ = (0.011495536452803) x5
x5 = 8.30 x 10⁻⁵/0.011495536452803
x5 = 0.007220193710904
From the above results;
a. x3 and x4 are the first to agree to two significant figures
b. x4 and x5 are the first to agree to three significant figures
Food contains chemical potential energy that the body uses. How do you think that the body gains this energy? Propose an explanation.
Answer:
The body gain the energy through the digestion of the food we eat and when it is breakdown it releases energy.
Explanation:
The food we consumed is digested by the activities of acids and enzymes in the stomach.
Carbohydrates are the primary source of body energy.
When it is eaten, it digestion starts from the mouth when it mixed with the saliva released from the salivary gland and salivary amylase acts on it.
When it's get to the stomach/ intestine, it is further breakdown through the activities of enzymes into glucose.
The stomach and the intestine absorb the glucose and release it into the blood stream. Glucose can be use as energy source or stored later and insulin help to release it.
Answer:
Explanation:
When the food substances (for example carbohydrate) that contain chemical potential energy are broken down, they produce glucose. Carbohydrate is the major source of glucose for the body, the digestion of carbohydrate begins in the mouth in the presence of the enzyme called amylase.
When glucose is produced from carbohydrate breakdown, the glucose is picked up by insulin which allows the glucose enters the cells. In the cells, these glucose molecules undergo glycolysis (glucose breakdown/catabolism) in order to produce ATP (high energy molecules that provides energy for all cell). When ATP is produced, the cells use the ATP to carry out several body and biological functions. These multi-enzyme steps explains how the body gains this energy.
A box has dimensions 0.2 mx 0.4 m x 0.6 m. What is the
volume of the box in cubic meters? Round to the nearest
hundredths.
Answer:
[tex]V=0.048m^3[/tex]
Explanation:
Hello,
In this case, since the volume is computed by multiplying the given dimensions as follows:
[tex]V=0.2m*0.4m*0.6m[/tex]
The result is shown in cubic meters since each meter is also added:
[tex]V=0.048m^3[/tex]
Best regards.
A sulfuric acid solution containing 571.6 g of H2SO4 per liter of aqueous solution has a density of 1.329 g/cm^3.Calculate:a. Mass percentageb. Mole fractionc. Molalityd. molarity of H2SO4 in this solution.
Given :
Mass of [tex]H_2SO_4[/tex] is 571.6 g per liter .
Density of solution , [tex]\rho=1.329\ g/cm^3[/tex] .
To Find :
a. Mass percentage
b. Mole fraction
c. Molality
d. molarity of H2SO4 in this solution.
Solution :
Molar mass of [tex]H_2SO_4[/tex] , m = 1329 g/mol .
a ) Mass of [tex]H_2SO_4[/tex] contain in 1 liter is 1329 g .
[tex]mass \ \%=\dfrac{571.6}{1329}\times 100=43.01 \%[/tex]
b ) Moles of [tex]H_2SO_4[/tex] = [tex]\dfrac{571.6\ g}{98\g/mol}=5.83\ mol[/tex] .
Moles of [tex]H_2O[/tex] = [tex]\dfrac{1329-571.6\ g}{18\ g/mol}=42.08\ mol[/tex] .
Mole fraction [tex]=\dfrac{5.83}{5.83+42.08}=0.12[/tex] .
c ) Molarity of [tex]H_2SO_4[/tex] [tex]=\dfrac{5.83\ mol}{1 \ L}=5.83\ M[/tex] .
Hence , this is the required solution .
Sulfur tetrafluoride, SF4, has a mass ratio of sulfur to fluorine of 1.00 : 2.37. A second, unknown compound containing sulfur and fluorine has a sulfur to fluorine mass ratio of 1.00 : 3.55. Use the law of multiple proportions to determine the chemical formula of the unknown compound.
Answer:
The formula of the unknown compound = SF₆
Explanation:
The law of multiple proportion states that if two elements A and B combine to form more than one compound, then the various masses of A which combine with a fixed mass of B are in simple multiple ratio.
In the compound SF₄, the mass ratio of sulfur to fluorine is 1.00 : 2.37
In the unknown compound, the mass ratio of sulfur to fluorine is 1.00 : 3.55
Since the number of sulfur atoms in the two samples are fixed;
The ratio of fluorine in the unknown sample and SF₄ = 3.55/2.37 = 3/2
Therefore, the number of fluorine atoms in the unknown sample = 4 * 3/2 = 6 atoms
The formula of the unknown compound = SF₆
The formula of the unknown compound = SF₆
The calculation is as follows:In the compound SF₄, the mass ratio of sulfur to fluorine is 1.00 : 2.37
In the unknown compound, the mass ratio of sulfur to fluorine is 1.00 : 3.55
Since the number of sulfur atoms in the two samples are fixed;
Now
The ratio of fluorine in the unknown sample and SF₄ = [tex]3.55\div 2.37 = 3\div 2[/tex]
So, the number of fluorine atoms in the unknown sample should be
= [tex]4 \times 3\div 2 [/tex]
= 6 atoms
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Who.
am I? Most of us are solids, shiny, malleable, ductile, good conductors of heat and electricity. A) metals
B) nonments
C) metalloids
Answer:
Metals if you dont beleive me here is a picture to prove it
Explanation:
Most of us are solids, shiny, malleable, ductile, and good conductors of heat and electricity. They are metals. The correct option is A).
What are metals?Metals are those periodic table elements that are malleable, pliable, and ductile because they have valence electrons in their outermost shells, metals are those periodic table elements that are malleable, pliable, and ductile.
They are also exceedingly reactive. In the middle of the periodic table, they can be found. Examples are magnesium, titanium, iron, zinc, and bronze.
Metals can be used to create a variety of items, including jewelry, via foil paper gates. The world's most practical metal is still steel. Non-metals and metalloids do not have these given characteristics.
Thus, the correct option is A) metals.
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How do molecules of varying sizes separate in electrophores?
Answer:
Smaller molecules migrate through the gel more quickly and therefore travel further than larger fragments that migrate more slowly and therefore will travel a shorter distance. As a result the molecules are separated by size.
Explanation:
6. Match the si base units below with their functions.
second distance-
meter temperature-
kilogram time -
kelvin mass-
liter volume-
To solve this we must be knowing each and every concept related to International System of Units. Therefore, in the below given ways matching can be done.
What is SI unit?A metric system that is utilized as a recognized international measuring standard is known as the International System of Units (SI). The English translation of the French word Systeme International is SI unit.
It is essential for the advancement of technological and scientific research in order to prevent misunderstanding within units. It has 22 derived units defined by 7 basic units.
distance- metre (m)
temperature- Kelvin (K)
time - second(s)
mass- kilogram (Kg)
volume- liter (l)
Therefore, in the above given ways matching can be done.
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((Please help asap! Giving brainliest))
Which of the following explains how Albert Einstein tried to influence the use of his discovery of the energy equation? (5 points)
Select one:
a. He opposed the use of nuclear fusion during the Manhattan Project.
b. He recommended uncontrolled fusion for medical testing and treatment.
c. He recommended applying the principles of nuclear fission to defend against enemies.
B
i hope this helped!
None of the above are correct.
Albert Einstein supported the use of radioactive elements for medical diagnostic purposes.
I hope this helps, good luck!
5. Work this problem involving scientific notation:
The mass of a proton (M)is 0.000 000 000 000 000 000 000 000 001 673 kg. The mass of a neutron (M)is 0.000 000 000 000 000 000 000 000 001 675 kg. Convert each mass to
scientific notation, then calculate the difference in mass between the two particles.
2.000 x 10-20 kg
2.000 x 105 kg
2.000 x 10-kg
2.000 x 10-kg
2.000 10-kg
Answer:
The answer would be 2.000 x 10^-30
Explanation:
I had taken the test and got it correct.
a compound contains 70.0 or iron and 30.1 oxygen what is its empirical formula
Answer:
The empirical formula would be Fe2o3
Explanation:
you first take the grams or the percent of each element, then transform them from grams to moles.
After getting the number of mols you want to divide each mol by the lowest number of mol.
EX) for this problem the number of moles of Fe(iron) would be 1.253 mol and the moles for the oxygen would be 1.881 mol... so you take the lowest, 1.253, and divide both to get what's called a mol fraction.
1.253/ 1.253 =1Fe
1.881/ 1.253= 1.5
now we want a whole number since we're finding the formula of a compound... and since there is a 1.5 you would multiple that by 2 giving you 3 for oxygen and giving you 2 for iron.
then these whole numbers will give you the subscripts that's needed for your empirical formula :)
- Hope this helps!!!
PLZ HELP CHEMISTRY! WILL REWARD! Please correct me if I'm wrong.
I marked my answers as x.
1. During a titration, 50.0 ml of 0.2M NaOH were required to neutralize 50.0ml of H3PO4. What's the concentration of the H3PO4 solution?
A. 1.8M
B. 0.6M
C. 0.07M
x D. 0.2M
2. Attached photo - Using the two cell reduction potentials shown for their corresponding reaction, calculate the cell potential for a voltaic cell made from these two systems.
A. –1.68 V
B. –0.78 V
C. 0.78 V
D. 1.68 V
3. If atoms from two different elements react to form a compound, the element with a higher _______ will have a negative oxidation number.
A. atomic number
B. atomic radius
C. energy
x D. electronegativity
4. During the electrolysis of an aqueous solution of sodium nitrate, a gas forms at the anode, what gas is it?
x A. Oxygen
B. Hydrogen
C. Sodium
D. Water
5. The lithium-ion in a lithium-ion battery moves from one side to the other by
A. moving through the cathode.
B. moving through the anode.
x C. passing through the separator.
D. passing through the device.
6. The use of water in a heat exchanger is taking advantage of water's
x A. high specific heat.
B. significant expansion during boiling.
C. solid state when frozen.
D. polar molecular nature.
Which of the following goes through the largest volumetric change?
A. Water when it boils into steam
x B. Water when it freezes into ice
C. Water when it's heated from 1oC to 99oC
D. Ice when it melts into water
Explanation:
1. During a titration, 50.0 ml of 0.2M NaOH were required to neutralize 50.0ml of H3PO4. What's the concentration of the H3PO4 solution?
Answer:
Using CaVa / CbVb = Na / Nb. The correct option is D.
3. If atoms from two different elements react to form a compound, the element with a higher _______ will have a negative oxidation number.
Answer:
The correct option is electronegativity. For example, in H2O. Oxygen would have a negative oxidation number of -2 because it is highly electronegative compared to hydrogen. Also, a negative oxidation number means it gains electrons.
4. During the electrolysis of an aqueous solution of sodium nitrate, a gas forms at the anode, what gas is it?
Answer:
At the anode, OH- ions are preferentially discharged. They lose electrons there and form oxygen gas. The correct option is A. Oxygen
5. The lithium-ion in a lithium-ion battery moves from one side to the other by
Answer:
The correct option is passing through the separator. The lithium ions, moves from the anode to the cathode when in use.
6. The use of water in a heat exchanger is taking advantage of water's
Answer:
The correct option is it's High specific heat capacity. Since heat exchangers requires transfer of heat, there is need for a medium that is able to carry this heat. The hydrogen bonds in water provides it with an abnormal high specific heat capacity.
7. Which of the following goes through the largest volumetric change?
Answer:
Whenever ice melts it occupies the same energy as when it was frozen. When water is heated from 1oC to 99oC there is no change in volume. Volume of water increases abruptly at it boils at 100oC and changes its state from liquid water to steam. When water freezes it's volume increases by approximately 9%. The correct option is A.
Kindly Note:
Next time, You don't have to ask everything in a single question. Nobody would want to go through the stress of answering them all. I omitted number 2 intentionally.
How many atoms are there in 3.559*10^-6 mol of krypton?
Answer:
The answer is
[tex] 2.143 \times {10}^{18} \: \: atoms[/tex]Explanation:
To find the number of atoms given the number of moles we use the formula
N = n × L
where
N is the number of entities
n is the number of moles
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question
[tex]n = 3.559 \times {10}^{ - 6} \: mol[/tex]
Substitute the values into the above formula and solve
That's
[tex]N = 3.559 \times {10}^{ - 6} \times 6.02 \times {10}^{23} \\ = 2.1425 \times {10}^{18} [/tex]We have the final answer as
[tex]N = 2.143 \times {10}^{18} \: \: atoms[/tex]Hope this helps you
Give one example of a Phase Change
Para regular el contenido de minerales en el agua destinada a la producción de una cerveza se emplean soluciones de cloruro de calcio. Si se dispone de una solución de CaCl2 5,00 % m/V, y se desea obtener 4,00 L de una solución 5,00x10-3 M en aniones cloruro, ¿qué volumen de solución concentrada se necesita, expresado en mililitros?
Answer:
22.2mL de la solución concentrada se requieren
Explanation:
Lo primero que debemos hacer para solucionar este problema es convertir el 5.00% m/v de CaCl₂ a molaridad de Cl⁻:
5g/100mL = 50g/L
Masa molar CaCl₂: 110.98g/mol.
50g * (1mol / 110.98g) = 0.45 moles CaCl₂/L = 0.45M* 2 = 0.90M Cl⁻ (Se multiplica por dos ya que son dos moles de Cl⁻ por mol de CaCl₂
Ahora, si deseas 4.00L de una solución 5.00x10⁻³M, necesitas:
4.00L * (5.00x10⁻³ moles Cl⁻ / L) = 0.02 moles Cl⁻
Como estas moles vienen de la solución 0.90M:
0.02 moles Cl⁻ * (1L / 0.90 moles) = 0.0222L =
22.2mL de la solución concentrada se requierenA nickel is found to have a volume of 0.728 milliliters.
Set up the problem below and calculate the volume of the nickel in liters.
0.728 mLx
Drag and drop your selection from the following list to complete the answer:
1000 L
1 mL
1000 mL
1L
Answer:
7.28×10¯⁴ L
Explanation:
From the question given above, the following data were obtained:
Volume of Nickel (mL) = 0.728 mL
Volume of Nickel (L) =.?
The volume of nickel in litres (L) can be obtained by converting 0.728 mL to L. This can be obtained as follow:
1000 mL = 1 L
Therefore,
0.728 mL = 0.728 mL × 1 L / 1000 mL
0.728 mL = 7.28×10¯⁴ L
Therefore, 0.728 mL is equivalent to 7.28×10¯⁴ L.
what is Boyle's law
law stating that the pressure of a given mass of an ideal gas is inversely proportional to its volume at a constant temperature
Answer:
Boyle's law is a pressure versus volume relationship. The law was discovered by Robert Boyle in the 17th century. It states the pressure of a fixed amount of a gas is inversely proportional to its volume at a constant temperature.
Explanation:
pressure versus volume relationship
What happens to nonpolar molecules in water?
Answer:
B) They aggregate together.
Explanation:
A nonpolar molecule refers to a molecule in which there is no charge separation that means no positive or negative poles are created
Also it cannot create the bonds of hydrogen with the water molecules that results in the disturbance of normal structure of water that makes the water to create a fixed cage of molecules that are hydrogen bonded around it
Therefore in the given case, the option B is correct
A student performs a chemical reaction with vinegar and an antacid tablet. Experimental results are displayed in the table
below.
Before Chemical Reaction
Mass of Vinegar (9)
Mass of Antacid Tablet (g)
75.83
1264
After Chemical Reaction
Mass of Chemical Reaction (kg)
ODBB7
1 Explain how this chemical reaction represents the law of conservation of matter.
The mass
Answer:
Explanation:
Please tell me if im wrong
Question 6. 6. In a reaction between vinegar and antacid tablets, the antacid is the limiting reagent. At constant pressure and temperature, three tablets produce 600 cm3 of gas. What volume will two tablets produce?
(Points : 3)
400 cm3
600 cm3
800 cm3
1,200 cm3****
Question 7. 7. You breathe in 3.0 L of pure oxygen at 298 K and 1,000 kPa. How many moles of oxygen did you take in? (Use the ideal gas law: PV = nRT where R = 8.31 L-kPa/mol-K.)
(Points : 3)
0.05 moles
1.21 moles*****
2.42 moles
20.0 moles
Question 8. 8. Consider a gas at STP in a container of 22.4 L. If you apply the ideal gas law, what is the approximate value of n?
(Points : 3)
0.5
8.31
224****
1
Question 9. 9. Water boils at 100°C. What is that temperature on the Kelvin scale?
(Points : 3)
213 K
325 K****
333 K
373 K
Question 10. 10. The average speeds of gas molecules in cylinders A, B, C, and D are 0.001 m/s, 0.05 m/s, 0.1 m/s, and 0.5 m/s, respectively. Which cylinder contains gas that is closest to absolute zero?
(Points : 3)
A
B
C******
D
I suck at chemistry
...Show more
What is an atomic change?
DO NOT COPY AND PASTE FROM GOOGLE, THAT DOESN'T HELP.
Explanation:
Atomic change is indivisible change and can NEVER partly succeed it can only fully succeed or Not succeed at all.
You need to prepare an acetate buffer of pH 5.24 from a 0.796 M acetic acid solution and a 2.65 M KOH solution. If you have 830 mL of the acetic acid solution, how many milliliters of the KOH solution do you need to add to make a buffer of pH 5.24 ? The pKa of acetic acid is 4.76. Be sure to use appropriate significant figures
Answer:
187.3mL of 2.65M KOH you must add
Explanation:
The pH of the buffer of acetic acid is obtained as follows:
pH = pKa + log [Acetate] / [Acetic Acid]
Where [] could be moles of acetate and acetic acid
Replacing:
5.24 = 4.76 + log [Acetate] / [Acetic Acid]
0.48 = log [Acetate] / [Acetic Acid]
3.01995 = [Acetate] / [Acetic Acid](1)
As concentration of acetic acid is 0.796M and volume is 830mL, the moles of acetic buffer is:
0.830L * (0.796 moles / L) = 0.6607 moles
Thus:
0.6607 moles = [Acetate] + [Acetic Acid] (2)
Replacing (2) in (1):
3.01995 = 0.6607 moles - [Acetic Acid] / [Acetic Acid]
3.01995 [Acetic Acid] = 0.6607 moles - [Acetic Acid]
4.01995 [Acetic Acid] = 0.6607 moles
[Acetic Acid] = 0.16435 moles
[Acetate] = 0.6607 moles - 0.16435 moles = 0.49635 moles
The reaction of acetic acid with KOH to produce Acetate is:
Acetic acid + KOH → Acetate + Water
That means the moles of KOH you add, are the moles of acetate.
To add 0.49635 moles of 2.65M of KOH you need:
0.49635 moles * (1L / 2.65 moles) = 0.1873L =
187.3mL of 2.65M KOH you must addA chemical plant produces an ammonia‑rich waste gas that cannot be released as is into the environment. One method to reduce the ammonia concentration in the waste gas is to bubble the waste gas though a liquid solvent. Components of the gas that are highly soluble, like ammonia, will dissolve into the liquid phase. Water is an appropriate liquid solvent for this process. The chemical plant produces 125.0 m3/h125.0 m3/h of waste gas (????=0.0407 mol/L)(rho=0.0407 mol/L) initially having a mole fraction of 0.200 NH30.200 NH3 and wishes to remove 90.0% of the initial amount of NH3.NH3. The maximum concentration of ammonia in water at this temperature is 0.4500 mol NH3/mol water.0.4500 mol NH3/mol water. Neglect the absorption of other waste gas components into the water and the evaporation of water into the waste gas stream. At what rate is NH3NH3 being removed from the feed gas? rate of NH3NH3 removal: mol/hmol/h What is the minimum flow rate of water (????=0.990 g/mL)(rho=0.990 g/mL) required to scrub out 90.0% of the incoming NH3?NH3? minimum flow rate of water: L/hL/h What is the mole fraction of NH3NH3 in the scrubbed waste gas stream? mole fraction: mol NH3mol waste gas
Answer:
Follows are the solution to this question:
Explanation:
In first point:
Ammonia volumetric flow = [tex]{105} \frac{m3}{h} = \frac{7}{240} \ \frac{m^3}{ s}[/tex]
Waste gas mole density, dw[tex]= 0.0407 \ \frac{mol}{L} = {40.7} \ \frac{mol}{m^3}[/tex]
Original ammonia mole proportion in receiving waste gas [tex]= 0.120[/tex]
Mole density for ammonia [tex]= 0.120 \times 40.7[/tex]
[tex]= 4.884 \ \ \frac{ \ mol}{ m^3 \text {of its incoming waste}}[/tex]
Therefore, ammonia rate is extracted from its incoming stream
[tex]= NH_3 \text{molecule density} \times \text {Volume flow rate} \\\\ = 4.884\times (\frac{7}{240})\\\\ = 0.14245 \ \ NH_3 \ \ \text{moles per second}[/tex]
As 90 percent ammonia is removed, that ammonia removal rate:
[tex]= 0.9 \times 0.14245 \\\\ = 0.128 \ \ NH_3 \ \text{moles per second} \\\\ = 460.8 \ \ \frac{mol}{h}[/tex]
In second point:
Ammonia possessing water content [tex]= 0.35\ \ \frac{NH_3}{mole}[/tex]
Consequently, to maintain 0.128 mol ammonia:
water moles necessary [tex]= \frac{1}{0.35} \times 0.128[/tex]
[tex]= 0.365 \ mol \ water[/tex]
Water atomic weight=[tex]18 g[/tex]
Therefore, mass needed of water [tex]= 18 \times 0.365[/tex]
[tex]= 6.57 \ g[/tex]
In this required water range of competencies stream rate:
[tex]= \frac{\text{necessary weight}}{\text{water density}} = \frac{6.57}{0.99} \\\\ = 6.63 \frac{ml}{second} \\\\ = 6.63 \times 10^6 \times 3600 \\\\ = 0.023868 \frac{m^3}{h} \\\\ = 23.868 \frac{L}{h}[/tex]
In third point:
fresh ammonia mol fraction [tex]= \frac{ \text{moles of ammonia from of the outgoing stream} }{\text{maximum moles}}[/tex]
Amino ammonia moles = 10 per cent of the ammonia moles inside an incoming stream = 0.10×initial concentration of the mole:
[tex]= 0.1 \times 4.884\\\\ = 0.484 \ moles[/tex] in an outgoing stream.
Its total outflow moles = the total ammonia moles at the original ammonia:
[tex]\text{stream moles} = 40.7- (90\% \times 4.884)[/tex]
[tex]= 36.3[/tex]
So new ammonina mole fraction:
[tex]= \frac{0.4884}{36.3} \\\\ = 0.01345[/tex]
3/5 of 1 1/9 + 3 1/2
Answer: 4 1/6
Explanation: 3/5x1 1/9=2/3. 2/3+3 1/2=4 1/6.
Which best explains why an electric toaster is considered a resistor?
It increases the flow of electrons.
It acts as a conductor.
It converts electric energy to another form of energy.
It produces an increase in voltage within the current.
Hi There!!
Your best answer choice is:
C. It converts electric energy to another form of energy.
Because, A electric toaster is considered a resistor because it coverts some of it energy into another form which is heat. a resistor is something that limits the flow of an electric current through a circuit.
[tex]GoodLuck!![/tex]
[tex]_{Loserbrazts}[/tex]
An electric toaster is considered a resistor because it converts electric energy to another form of energy. Therefore, the correct option is option C.
What is resistor?A "resistor" is a passive components electric device that is utilized to limit and regulate the electric current that flows in electrical circuits. It also allows us to provide a variable amount of resistance to something like an electrical circuit. Resistors are the most significant and widely utilized components in an electrical circuit.
The primary function of a resistor would be to decrease current flow but also voltage inside a specific area of the circuit. It is constructed of copper wires wound around with a ceramic rod and covered with insulating paint. Toaster converts electric energy to another form of energy.
Therefore, the correct option is option C.
To learn more about resistor, here:
https://brainly.com/question/27213213
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Temperature is the measure of average potential energy particles of a substance.
TRUE or FALSE
Answer:True
Explanation:
Answer: False
Explanation: Temperature is not the potential energy particles, it is the moving, or kenetic energy cells
Which is the property of nonmetals to evaporate easily.
Answer:
volatile
Explanation:
They are also poor conductors of electricity for they tend to form negative ions by gaining or sharing electrons [to be stable] unlike the metals. Hence, they have high ionization energy and high electronegativity values. In addition, nonmetals are usually volatile, which means that they evaporate easily
