Answer:
(b) 2.60%
Explanation:
Partition coefficient of the organic compound in ether is:
9.5 = Concentration in ether / Concentration in water
In the first extraction, X is the amount of organic compound extracted:
9.5 = X/50mL / (1-X)/200mL
9.5 = 200X / (50-50X)
475 - 475X = 200X
475 = 675X
X = 0.7037g are extracted.
Remains = 1g - 0.7037g = 0.2963g
Second extraction:
9.5 = X/50mL / (0.2963-X)/200mL
9.5 = 200X / (14.815-50X)
140.74 - 475X = 200X
140.74 = 675X
X = 0.2085g are extracted.
Remains = 0.2963g - 0.2085g = 0.0878g
Third extraction:
9.5 = X/50mL / (0.0878g-X)/200mL
9.5 = 200X / (4.3899-50X)
41.70 - 475X = 200X
41.70 = 675X
X = 0.2085g are extracted.
Remains = 0.0878g - 0.0618g = 0.026g remains
Percentage: 0.026g / 1g * 100 =
(b) 2.60%what is the president for 2020
Answer:
joe biden
Explanation:
It was DONALD TRUMP :) But Joe Biden got elected :(
By what mechanism does cyclohexanol react when treated in concentrated sulfuric acid/phosphoric acid and what compound results?
Answer:
The mechanism is E1 and the product is cyclohexene
Explanation:
Attached to this answer is an image of the reaction mechanism of the reaction between cyclohexanol and concentrated sulfuric acid/phosphoric acid. The acid (H3O^+) acts as catalyst.
We can see that the first step in the mechanism is the protonation of the -OH group of the alcohol. This is followed by loss of water molecule which is a good leaving group.
The water now acts as a Lewis base by abstracting a proton from the substrate, forming cyclohexene and regenerating the acid catalyst.
How many atoms are in this given equation 6Mn3C2
Answer:
There are three atoms in the equation
The volume of a gas decreases to half of its original volume, but the gas maintains the same
number of moles and temperature. According to the ideal gas law, what will most likely
happen to the pressure?
A. It will double.
B. It will decrease.
C. It will increase slightly.
D. It will remain the same.
Answer:
c
Explanation:
it will slightly increase
Answer:
A
It will double
It is possible for gases in the atmosphere to change the behavior of energy on earth. Agree or disagree
Answer:
I agree
Explanation:
because the sunlight passes through the atmosphere and is absorbed by earth's surface.
The green house gases in the atmosphere can change the behavior of energy on earth. Thus i agree with this statement.
What is green house effect?The green house effect is defined as a process by which the radiations from the sun are absorbed by the green house gases like methane, Chloro fluoro carbons and not reflected back into the space. This makes the surface as insulator and prevents it from freezing.
Due to the increased level of green house gases, the temperature of the earth increases considerably and thereby causes global warming, depletion of ozone layer, smog and air pollution, etc.
It is the natural green house effect which affect the behaviour of heat energy radiated by the sun. The green house gases never let the radiations escape from the earth and increase the surface temperature of earth. This leads to global warming.
Thus green house gases affects the solar energy.
To know more about Global warming, visit;
https://brainly.com/question/21476905
#SPJ6
10 things you should never do while making a measurement in chemistry
Answer:
Measure at the top of the meniscus
Hold the container (it is unsteady)
Explanation:
I'm really, really, sorry. I took chemistry in 6th grade and I'm in 8th, and I don't remember the entire list. This is all I could think of.
The specific rotation of (S)-2- butanol is + 13.5. If 1.00 g is dissolved in 10.0 mL of ethanol and placed in a sample cell with a length of 1.00 dm, what observed rotation do you expect?
Answer:
-1.35 degree
Explanation:
Given the specific rotation of (S)-2-butanol = +13.5 degree
So, the specific rotation of its enantiomer (R)-2-butanol = -13.5 degree
Now the optical rotation of a pure liquid is given by
[tex]$\theta = [\alpha]_\lambda ^t.l.d$[/tex]
Here, [tex]$\theta$[/tex] = the optical rotation
[tex]$[\alpha]_\lambda^t$[/tex] = specific rotation at temperature 't' and wave length 'λ'
= -13.5 degree
l = optical path length
= 1 dm
d = density
= 1/10
Therefore,
[tex]$\theta = -13.5 \times 1 \times \frac{1}{10}$[/tex]
= -1.35 degree
When a sample of liquid is heated, its thermal energy _______.
Answer:
Entropy.
Explanation:
I really hope this is right! sorry if its wrong
When a sample of liquid is heated, its thermal energy: increases.
Thermal energy can be defined as the energy possessed by an object due to the movement of its particles.
Basically, the temperature of an object or system is highly dependent on thermal energy.
Hence, temperature is directly proportional to thermal energy.
Additionally, as the temperature of an object increases due to the application of heat, the thermal energy of the object increases.
In conclusion, thermal energy increases when a sample of liquid is heated.
Read more: https://brainly.com/question/22077574
A solution of hydrochloric acid of unknown concentration was titrated with 0.16 M NaOH. If a 350-mL sample of the HCl solution required exactly 17 mL of the NaOH solution to reach the equivalence point, what was the pH of the HCl solution?
Answer:
The correct answer is 2.1
Explanation:
The neutralization reaction involved in the titration is between a strong acid (HCl) and a strong base (NaOH), as follows:
HCl + NaOH → NaCl + H₂O
According to this, 1 equivalent of HCl reacts with 1 equivalent of NaOH. The equivalence point is the point at which the amount of NaOH added reacted completely with the amount of HCl.
moles of acid = moles of base
moles HCl = moles NaOH
Ca x Va = Cb x Vb
Ca = (Cb x Vb)/Va = (0.16 M x 17 mL)/(350 mL) = 7.8 x 10⁻³ M
Since HCl is a strong acid, we calculate the pH of the solution directly from the concentration of acid:
[H⁺]= Ca = 7.8 x 10⁻³ M
pH = -log [H⁺] = -log (7.8 x 10⁻³ M) = 2.11
Therefore, the pH of the HCl solution is 2.1
Calculate the density of the rock if its mass is 360 g.
Answer:
12.0 g/mL
Explanation:
From the question given above, the following data were obtained:
Mass of Rock = 360 g
Volume of water = 150 mL
Volume of water + Rock = 180 mL
Density of Rock =?
Next, we shall determine the volume of the rock. This can be obtained as follow:
Volume of water = 150 mL
Volume of water + Rock = 180 mL
Volume of Rock =?
Volume of Rock = (Volume of water + Rock) – (Volume of water)
Volume of Rock = 180 – 150
Volume of Rock = 30 mL
Finally, we shall determine the density of the rock as illustrated below:
Mass of Rock = 360 g
Volume of Rock = 30 mL
Density of Rock =?
Density = mass /volume
Density of Rock = 360 / 30
Density of Rock = 12.0 g/mL
Thus, the density of the rock is 12.0 g/mL
The autoignition of both ethanol and octane occurs at 363 oC. Which gas sample contains the gas molecules that have a greater average kinetic energy
Answer:
See explanation
Explanation:
At the same temperature, the average kinetic energy of gases depends on the molecular mass of the gas. Hence, given a particular temperature, lighter molecules travel faster on the average than heavier molecules.
Considering ethanol and octane, The molar mass of ethanol is 46.07 g/mol while the molar mass of octane is 114.23 g/mol. Hence, ethanol has a greater average kinetic energy than octane at the same temperature.
Which statement describes how phase changes
can be diagrammed as a substance is heated?
The phase is on the y-axis and thew
temperature is on the x-axis.
The temperature is on the y-axis and the
phase is on the x-axis.
The time is on the y-axis and the temperature
is on the x-axis.
The temperature is on the y-axis and the time
is on the x-axis
Answer: D
Explanation:
On edge
Answer:
D
Explanation:
just did it on Ed
Which of the following accurately pairs the part of an atom to its charge? A. Proton—no charge B. Neutron—positive charge C. Electron—negative charge D. Electron—no charge
Answer:
I think it's c but I'm not sure
Answer: C
Explanation:
branches of sicence
Answer:
Natural science can be divided into two main branches
Explanation:
life science and physical science. Life science is alternatively known as biology, and physical science is subdivided into branches: physics, chemistry, astronomy and Earth science.
Answer:
Astronomy
Biology
Geology
Chemistry
Please Mark Brainliest and rate me 5
Thank You Good Night / Good Day to you
Which two types of energy are formed by the transformation shown in the
photo?
A. Chemical energy →
thermal energy
n BiThermal energy
electrical energy
C. Thermal energy – chemical energy
D. Chemical energy - electromagnetic energy
SUBMIT
Answer:
A. Chemical Energy --> Thermal Energy
D. Chemical Energy --> Electromagnetic Energy
Explanation:
I took the quiz!
Johnny has thrown a 2kg ball. The ball has an acceleration of 20m/s2. How much was the force that Johnny used?
Answer:
The answer is 40 NExplanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question we have
force = 2 × 20
We have the final answer as
40 NHope this helps you
Answer: 40N
Explanation:
Force = mass × acceleration
20 x 2 = force
20 x 2 is 40
Answer 40 N
NOT 40J
what is the the correct equation for water gas
Answer:
Water-gas A mixture of carbon monoxide (CO) and hydrogen (H2) produced by passing steam over red-hot coke using the endothermic reaction C + H2O → CO + H2.
Visible light has an average wavelength of 550 nm. How much energy would be in this wavelength of light? 5 x 10-19
Answer:
E = 3.6×10⁻¹⁹ J
Explanation:
Given data:
Wavelength = 550 nm (550 ×10⁻⁹ nm)
Energy of wave = ?
Solution:
Formula:
E = h c/λ
c = 3×10⁸ m/s
h = 6.63×10⁻³⁴ Js
Now we will put the values in formula.
E = 6.63×10⁻³⁴ Js × 3×10⁸ m/s /550 ×10⁻⁹ nm
E = 19.89×10⁻²⁶ J.m /550 ×10⁻⁹ nm
E = 0.036×10⁻¹⁷ J
E = 3.6×10⁻¹⁹ J
Please i really need help
it's due today
Answer:
coke and mentos are basically just a small scale replica
Explanation:
What mass of a solution labeled 6.3% sucrose (C12H22O11, 342 g/mol) by mass contains 11.0 g of sucrose?
Answer:
174.6g of solution contains the 11.0g of sucrose
Explanation:
A solution of 6.3% by mass of sucrose contains 6.3g of sucrose in 100g of solution, that is, 6.3g of sucrose / 100g of solution.
As we want to find the mass contains 11.0g of sucrose, we can write:
11.0g of sucrose * (100g of solution / 6.3g of solution) =
174.6g of solution contains the 11.0g of sucroseWhat does animals exhale?
Answer:
Carbon dioxide
Explanation:
Humans are animals and we exhale carbon dioxide
In the lab you react 20g of potassium iodide with an excess of lead (II) nitrate to form 15g of lead (II) iodide precipitate. What is the percent yield of your experiment?
What is the balanced equation for this question?
What is the first ratio used to solve this question?
What is the second ratio used to solve this question?
What is the third ratio used to solve this question?
What is the percentage yield?
Answer:
C
Explanation:
Examples of solutions can be:
O A. a solid dissolved in a liquid
O B. gas mixed with a liquid
O C. liquid mixed with a liquid
OD. all of the the above
Answer:
B. gas mixed with a liquid
Explanation:
because:
A. a solid can't dissolve in a liquid.
C. two liquids mixed isn't a solution
D. Not All of the above for sure.
Examples of solutions can be all of the above. The correct option is D.
What is a solution?A solution is made when a solute is mixed with a solvent. The solution can be a liquid, solid, or gas. The solution is made when the solute is fully mixed with the solvent. The solute is the substance that gets mixed, and the solvent is the base in which the solute gets dissolved.
So, a solid dissolved in a liquid, gas mixed with a liquid, or a liquid mixed with a liquid, the energy statement is true for a solution.
Examples of a solution are sugar dissolved in water when water mix with soda and state gets mixed with water or another gas.
Thus, the correct options are D. all of the the above.
Learn more about the solution, here:
https://brainly.com/question/1416865
#SPJ2
How to remove filter of the text
Go to the Data tab > Sort & Filter group, and click Clear.
Go to the Home tab > Editing group, and click Sort & Filter > Clear.
2. Which of the following would produce a precipitate when mixed water (H20)?
A) HNO3
B) Br2
C) BaS
D) PbBr2
3.Given that the reaction below is a precipitation reaction, what is the missing symbol?
Li2CO3 (aq) + BaS (aq) - > LiOH (aq) + BaCo3 (?)
Answer: #2 : s, solid & #3 : PbBr2
Explanation:
In the reaction [tex]\rm Li_2CO_3 (aq) + BaS (aq)\rightarrow LiOH (aq) + BaCo_3 (?)[/tex] the missing symbol is s . The PbBr₂ will produce a precipitate when mixed water. Hence option D is correct.
What is chemical reaction?Chemical reaction is defined as a procedure that involves changing a substance's molecular or ionic structure, as opposed to changing its physical shape or undergoing a nuclear reaction. When atoms establish or break chemical bonds, chemical reaction take place. Reactants are the substances that begin a chemical reaction, while products are the compounds that are created as a result of the reaction.
Precipitation is defined as the mechanism by which water vapor in the atmosphere condenses and descends to the ground under the pull of gravity. Water vapor in the clouds condenses into increasing-sized droplets of water, forming precipitation. To replenish the water on the earth, precipitation is required. This world would be a vast desert if it didn't rain. Within an estuary, water level and water quality are impacted by the frequency and length of precipitation events.
Thus, in the reaction [tex]\rm Li_2CO_3 (aq) + BaS (aq)\rightarrow LiOH (aq) + BaCo_3 (?)[/tex] the missing symbol is s . The PbBr₂ will produce a precipitate when mixed water. Hence option D is correct.
To learn more about chemical reaction, refer to the link below:
https://brainly.com/question/3461108
#SPJ6
Ammonia (NH3) is the active cleaning ingredient in Windex and is also the main contributor to the odor of stale cat urine. Ammonia has a ΔH°vap of 23.35 kJ/mol and a ΔS°vap of 97.43 J/mol·K. What is the normal boiling point of ammonia
Answer:
[tex]T_b=239.7K=-33.49\°C[/tex]
Explanation:
Hello!
In this case, since the relationship between entropy and enthalpy for any process is defined below:
[tex]S=\frac{H}{T}[/tex]
For the vaporization of ammonia or any liquid, we can write:
[tex]\Delta S_{vap}=\frac{\Delta H_{vap}}{T_{vap}}[/tex]
In such a way, solving the temperature of vaporization, or boiling point, we have:
[tex]T_{vap}=\frac{\Delta H_{vap}}{\Delta S_{vap}}[/tex]
Plugging in the given enthalpy and entropy of vaporization we obtain:
[tex]T_{vap}=T_b=\frac{23350\frac{J}{mol} }{97.43\frac{J}{mol*K}} \\\\T_b=239.7K=-33.49\°C[/tex]
Best regards!
From the information provided in the question, the boiling point of ammonia is 240 K.
Entropy is the degree of disorderliness in a system. The entropy of a system can be obtained using the relation;
ΔS°vap = ΔH°vap /T
Now;
ΔH°vap = 23.35 kJ/mol
ΔS°vap = 97.43 J/mol·K
T = ?
Making T the subject of the formula and substituting values;
T = ΔH°vap /ΔS°vap
T = 23.35 × 10^3J/mol/97.43 J/mol·K
T = 240 K
Learn more: https://brainly.com/question/11155928
How many liters of blood does a human body have
Answer:
20000
Explanation:
Which of the following is a chemical change? A. soil drying as water evaporates B. a rock eroding as the wind removes particles from it C. a solution of salt water being diluted as water is added to it D. silver tarnishing as the silver metal reacts with sulfur
Answer:
Its D
Explanation:
I took the quiz
Answer:
D
Explanation:
IT IS REACTING
what looks attractive on guys
Answer: for me everything ig
Explanation:
what is the atomic number of oxygen
Answer: The atomic number of oxygen is "O" .
Explanation:
Because Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds.