After recrystallizing an impure sample with isopropanol, you isolate your product by filtration. What solvent do you use to wash your crystals? Room temperature distilled water Room temperature isopropanol Ice cold distilled water Ice cold isopropanol
Answer:
The correct answer is ice cold isopropanol.
Explanation:
Any compound in the initial stage is first dissolved in any suitable solvent and is heated for a certain duration for the process of recrystallization. Afterward, the compound is kept at room temperature so that it gets cooled gradually. In the process, the impurities remain dissolved in the solvent and the pure compound gets separated in the form of a precipitate.
Post all this, the filtration of the pure compound is done and is then washed with the cold solvent, which was initially used to dissolve the compound. Therefore, the appropriate solvent to use in the process is ice-cold isopropanol.
If 196L of air at 1.0 atm is compressed to 26000ml, what is the new pressure
Answer:
7.5 atm
Explanation:
Initial pressure P1 = 1.0 ATM
Initial volume V1= 196 L
Final pressure P2= the unknown
Final volume V2= 26000ml or 26 L
From Boyle's law we have;
P1V1= P2V2
P2= P1V1/V2
P2= 1.0 × 196/26
P2 = 7.5 atm
Therefore, as the air is compressed, the pressure increases to 7.5 atm.
What is the systematic name of the following compound?
Mn3(PO4)2
The polyatomic ion phosphate has the formula PO
Answer:
Manganese(II) phosphate | Mn3(PO4)2 - PubChem
Answer:
Magnese(ll) posphate M23 (p042) Molecular weight.
That is what the leters stand for!
IF THIS HELPED AND IF YOU DON'T MIND CAN YOU PLEASE MARK ME BRAINLIEST?Coral reefs support more species per unit area than any other marine
environment on Earth. What role do coral reefs play in the health of the
biosphere?
A. Coral reefs tend to drain nearby wetlands of stagnant water.
B. Their productive organisms play a major role in nutrient recycling.
C. Their colorful organisms attract millions of tourists each year.
D. Coral reefs require very specific environmental conditions.
SUBMIT
Answer:
B. Their productive organisms play a major role in nutrient recycling.
Explanation:
Coral reefs contain photosynthetic algae that help coral reefs in processing nutrients and contribute in the nutrient cycle.
The process of photosynthesis in corals leads to carbon fixing in which corals transform, carbon dioxide, into organic carbon. carbon fixing property allows corals to become primary producers.
Dissolve organic matter produced by corals is consumed by several organisms such as crabs, worms, fish, and snails.
Hence, coral reefs maintain the flow of energy and nutrient cycle in the biosphere and the correct option is B.
If you prepare a solution by adding sufficient amount of solute so that after heating and cooling the solution there is a visible amount of solid solute left in the bottom of the beaker, the solution would be considered ________.
Answer:
saturated
Explanation:
What is it called when a gas changes into a liquid?
Answer:
Explanation:
Condensation is the word you seek.
Answer:
Condensation
Explanation:
When a gas is subjected to decrease in temperature it is condensed
Consider the reaction in a commercial heat pack: 4 Fe (s) + 3 O2(g) ® 2 Fe2O3 (s) DH = -1652 kJ a) How much heat is released when 1.00 g iron is reacted with excess O2? b) What mass of O2 must react with iron in order to generate 2150 kJ of heat?
Answer:
a) -7.395kJ of energy are released.
b) 125g of O₂ must react.
Explanation:
Based on the reaction:
4 Fe (s) + 3 O₂(g) → 2 Fe₂O₃ (s) ΔH = -1652 kJ
4 moles of iron with an excess of oxygen release -1652kJ of energy
a) The heat released is:
1.00g Fe (molar mass: 55.845g/mol)
1.00g × (1mol / 55.845g) = 0.0179 moles de Fe.
As 4 moles release -1652kJ, 0.0179 moles release:
0.0179 mol Fe × (-1652kJ / 4mol Fe) = -7.395kJ of energy are released.
b) As 3 moles of oxygen produce -1652kJ, 2150kJ are released when react:
2150kJ × (3 mol O₂ / 1652kJ) = 3.9 moles of O₂
As molar mass of O₂ is 32g/mol, mass of 3.9 moles of O₂ is:
3.9 mol O₂ × (32g / mol) = 125g of O₂ must react.
How many significant figures are in 382.90?
Answer:
5
Explanation:
Answer:
5
Explanation:
A filtration system continuously removes water from a swimming pool, passes the water through filters, and then returns it to the pool. Both pipes are located near the surface of the water. The flow rate is 15 gallons per minute. The water entering the pump is at 0 psig, and the water leaving the pump is at 10 psig.
A. The diameter of the pipe that leaves the pump is 1 inch. How much flow work is done by the water as it leaves the pump and enters the pipe?
B. The water returns to the pool through an opening that is 1.5 inches in diameter, located at the surface of the water, where the pressure is 1 atm. How much work is done by the water as it leaves the pipe and enters the pool?
C. "The system" consists of the water in the pump and in the pipes that transport water between the pump and the pool. Is the system at steady state, equilibrium, both, or neither?
Answer:
A . [tex]\mathbf{W = 7133.2 \dfrac{ft. lb_f}{min} }[/tex]
B. [tex]\mathbf{W = 4245.24 \dfrac{ft. lb_f}{min} }[/tex]
C. The system is at steady state but not at equilibrium
Explanation:
Given that:
The volumetric flow rate of the water = 15 gallons per minute
The diameter of the pipe that leaves the pump is 1 inch.
A. The objective here is to determine how much work flow is done by the water as it leaves the pump and enters the pipe
The work flow that is said to be done can be expressed by the relation :
W = P × V
where;
P = pressure
V = volume
Also the given outlet pressure is the gauge pressure
The pressure in the pump P is can now be expressed by the relation:
[tex]P_{absolute} = P_{guage} + P_{atmospheric}[/tex]
[tex]P_{absolute}[/tex] = 10 psig + 14.7 psig
[tex]P_{absolute}[/tex] = 24.7 psig
W = P × V
W = 24.7 psig × 15 gal/min
[tex]W = (24.7 \ psig * \dfrac{\frac{lb_f}{in^2}}{psig}) * ( 15 \frac{gal}{min}* \dfrac{0.1337 \ ft^3}{1 \ gal }* \dfrac{144 \ in^2}{1 \ ft^2})[/tex]
[tex]\mathbf{W = 7133.2 \dfrac{ft. lb_f}{min} }[/tex]
Thus ; the rate of flow of work is said to be done by the water at [tex]\mathbf{W = 7133.2 \dfrac{ft. lb_f}{min} }[/tex]
B.
Given that :
The water returns to the pool through an opening that is 1.5 inches in diameter.
where the pressure is 1 atm.
Then ; the rate of work done by the water as it leaves the pipe and enter the pool is as follows:
W = P × V
W = 1 atm × 15 gal/min
[tex]W = 1 \ atm * ( 15 \frac{gal}{min}* \dfrac{0.1337 \ ft^3}{1 \ gal }* \dfrac{144 \ in^2}{1 \ ft^2})[/tex]
[tex]\mathbf{W = 4245.24 \dfrac{ft. lb_f}{min} }[/tex]
Thus ; the rate of flow of work done by the water leaving the pipe and enters into the pool is at [tex]\mathbf{W = 4245.24 \dfrac{ft. lb_f}{min} }[/tex]
C.
We can consider the system to be at steady state due to the fact that; the data given for the flow rate and pressure doesn't reflect upon the change in time in the space between the pump and the pool.
On the other-hand the integral factor why the system is not at equilibrium is that :
the pressure leaving the pipe is different from that of the water at the surface of the pool as stated in the question.
Best example of potential energy?
Answer:
water stored in a dam
Explanation:
when the water is in dam it is ready to move bit is not moving
There are __________ moles of N atoms present in a 2.0 g C8H10O2N4.
Answer:
[tex]n_N=0.041molN[/tex]
Explanation:
Hello,
In this case, for this mole-mass relationship, we are able to compute the moles of nitrogen atoms by firstly obtaining the moles of the given compound, considering its molar mass that is 194 g/mol:
[tex]n_{C_8H_{10}O_2N_4}=2.0gC_8H_{10}O_2N_4*\frac{1molC_8H_{10}O_2N_4}{194gC_8H_{10}O_2N_4} =0.01molC_8H_{10}O_2N_4[/tex]
Then, by knowing that one mole of the given compound has four moles of nitrogen atoms, we apply the following relationship:
[tex]n_N=0.01molC_8H_{10}O_2N_4*\frac{4molN}{1molC_8H_{10}O_2N_4} \\\\n_N=0.041molN[/tex]
Best regards.
In which of these statements are protons, electrons, and neutrons correctly compared?
Quarks are present in protons and neutrons but not in electrons.
Quarks are present in protons, neutrons, and electrons.
Quarks are present in neutrons and electrons but not in protons.
Quarks are present in protons and electrons but not in neutrons
the second statement is the correct one quarks are needed to balance charges in all subatomic particles such as neutrons, protons and electrons
3.01 × 1023 molecules H2O
Answer:
0.5 mole
Explanation:
The question isn't even clear
But I'm guessing you want to ask the number of moles
n= Number of molecules/ Avogadros number
n= 1/2
You are trying to recrystallize compound X. You consider using ethyl acetate as your recrystallizing solvent and test a small amount of compound X with ethyl acetate. You find that compound X is soluble in ethyl acetate at room temperature and at boiling. Is ethyl acetate a good recrystallization solvent? No, the sample needs to be insoluble or sparingly soluble at room temperature so that the maximum amount of purified crystals form at room temperature and in the ice bath. Yes, you want the sample to fully dissolve at room temperature and boiling so that it will crystallize in the ice bath. Yes, you can only be sure that all the impurities dissolved if the sample is soluble at room temperature
Answer:
No, the sample needs to be insoluble or sparingly soluble at room temperature so that the maximum amount of purified crystals form at room temperature and in the ice bath.
Explanation:
For a solvent to be adequate it must completely dissolve the substance to be purified when it is hot, that is, at boiling temperature only. It should be practically insoluble when the solvent is cold or at room temperature. This must occur in this way since impurities must be removed by hot filtering or dissolved in the mother liquor.
AHP for the formation of rust (Fe2O3) is -826 kJ/mol. How much energy is
involved in the formation of 5.00 grams of rust?
A 25.9 kJ
B 25.9 J
C 66.0 kJ
D 66.0)
Answer:
A- 25.9 kJ
Explanation:
ΔH of formation is defined as the amount of energy that is involved in the formation of 1 mole of substance.
ΔH of rust is -826kJ/mol, that means when 1 mole of rust is formed, there are released -826kJ.
Moles of 5.00g of Fe₂O₃ (Molar mass: 159.69g/mol) are:
5.00g ₓ (1 mole / 159.69g) = 0.0313 moles of Fe₂O₃.
If 1 mole release -826kJ, 0.0313 moles release:
0.0313 moles ₓ (-826kJ / 1 mole) = -25.9kJ
Thus, heat involved is:
A- 25.9 kJwhat is the color of benzene and bromine
Explanation:
Benzene is colorless, with a sweet odour.
Color of Bromine is reddish brown .
Hope this helps.
Identify whether each species functions as a Brønsted-Lowry acid or a Brønsted-Lowry base in this net ionic equation. HF (aq) + SO32- ⇌ F- + HSO3- Brønsted-Lowry _____ Brønsted-Lowry _____ Brønsted-Lowry _____ Brønsted-Lowry _____ In this reaction: The formula for the conjugate _____ of HF is The formula for the conjugate _____ of SO32- is
Explanation:
A Bronsted-Lowry base is a substance that accepts a proton in the form of a hydrogen (H) atom.
On the other hand;
Bronsted-Lowry acid is the substance that donates the proton.
HF (aq) + SO32- ⇌ F- + HSO3-
In the forward reaction;
Bronsted-Lowry acid : HF
Bronsted-Lowry base: SO32-
In the backward reaction;
Bronsted-Lowry acid : HSO3-
Bronsted-Lowry base: F-
The conjugate base of HF is F-
The conjugate acid of SO32- is HSO3-
A vegetable soup recipe requires one teaspoonful of salt. A chef accidentally puts in one tablespoonful. Now the soup is much too salty.
a) What can the chef do to reduce the salty taste of the soup?
b) What effects would your suggestion in a) have on the soup?
Answer:
a. Put a piece of fresh sliced yam with a bore into it into the soup.
Explanation:
b. Osmosis may occur
The chef can put a slice of yam in the soup with a hole in it as it will absorb excess of salt by process of diffusion.
What is diffusion?
Diffusion is defined as the process of movement of molecules which takes place under concentration gradient. It helps in movement of substances in and out from the cell.The molecules move from lower concentration region to a higher concentration region till the concentration becomes equal.
There are 2 main types of diffusion:
1) simple diffusion-process in which substances move through a semi-permeable membrane without the aid of transport proteins.
2) facilitated diffusion- It is a passive movement of molecules across cell membrane from higher concentration region to lower concentration.
There are 2 types of facilitated diffusion one is osmosis and dialysis.
Learn more about diffusion,here:
https://brainly.com/question/14852229
#SPJ2
During which stage of the water cycle could water enter the atmosphere as a gas? A. transpiration B. precipitation C. accumulation D. condensation
Answer: Transpiration---A
Explanation: Transpiration is the process in the water cycle whereby plant loose(excess) water by evaporation through the stomata of their leaves since not all water absorbed by the root is actually used for growth in plants.In order to allow the intake of carbon-dioxide, water must exit the leaves through transpiration which then provides the plant with cooling, rigidity and maintaining the overall water balance of the plant.
Asbestosis is a lung disease caused by inhaling asbestos fibers. The US Department of Health and Human Services considers a particular form of asbestos to be a carcinogen. The composition of this form of asbestos is 26.31% Mg, 20.20% Is, 1.45% H and the rest of the mass is due to oxygen. The molar mass of the compound is 277 g/mol. What is the molecular formula for the carcinogenic form of asbestos
Answer: The molecular formula for the carcinogenic form of asbestos [tex]Mg_3Si_2H_4O_9[/tex]
Explanation:
a) If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
Mass of Mg = 26.31 g
Mass of Si= 20.20 g
Mass of H= 1.45 g
Mass of O= (100-(26.31+ 20.20+ 1.45)) = 52.04 g
Step 1 : convert given masses into moles
Moles of Mg=[tex]\frac{\text{ given mass of Mg}}{\text{ molar mass of Mg}}= \frac{26.31g}{24g/mole}=1.10moles[/tex]
Moles of Si=[tex]\frac{\text{ given mass of Si}}{\text{ molar mass of Si}}= \frac{20.20g}{28g/mole}=0.72moles[/tex]
Moles of H=[tex]\frac{\text{ given mass of H}}{\text{ molar mass of H}}= \frac{1.45g}{1g/mole}=1.45moles[/tex]
Moles of O=[tex]\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{52.04g}{16g/mole}=3.25moles[/tex]
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For Mg = [tex]\frac{1.10}{0.72}=1.5[/tex]
For Si =[tex]\frac{0.72}{0.72}=1[/tex]
For H=[tex]\frac{1.45}{0.72}=2[/tex]
For O =[tex]\frac{3.25}{0.72}=4.5[/tex]
The ratio of Mg : Si: H: O = 1.5 : 1 : 2 : 4.5
Converting them into whole numbers :
The ratio of Mg : Si: H: O = 3 : 2 : 4 : 9
Hence the empirical formula is [tex]Mg_3Si_2H_4O_9[/tex]
Empirical mass =[tex]3\times 24+2\times 28+4\times 1+9\times 16=276g[/tex]
Molecular mass = 277 g
[tex]n= \frac{\text {Molecular mass}}{\text {Empirical mass}}=\frac{277}{276}=1[/tex]
Thus molecular formula =[tex]1\times Mg_3Si_2H_4O_9=Mg_3Si_2H_4O_9[/tex]
When a saturated solution of NH4Br dissolved in 100 grams of water is cooled from 60°C to 30°C, how much NH4Br will precipitate?
Answer:
[tex]m_{precipitated}=24.8g[/tex]
Explanation:
Hello,
In this case, since at 60 °C, 108 grams of ammonium bromide are completely dissolved in 100 grams of water for a saturated solution, once it is cooled to 30 °C, wherein only 83.2 grams are completely dissolved in 100 grams of water, the following mass will precipitate:
[tex]m_{precipitated}=108g-83.2g\\\\m_{precipitated}=24.8g[/tex]
Best regards.
¿What are the units that make up the 3 quantities (mass, volume of a substance and density)?
Answer:
Grams , centimeters cubed, and grams per centimeter
Explanation:
Ammonia will decompose into nitrogen and hydrogen at high temperature. An industrial chemist studying this reaction fills a tank with of ammonia gas, and when the mixture has come to equilibrium measures the amount of nitrogen gas to be 13. mol. Calculate the concentration equilibrium constant for the decomposition of ammonia at the final temperature of the mixture.
Complete Question
The complete question is shown on the first uploaded image
Answer:
The concentration equilibrium constant is [tex]K_c = 14.39[/tex]
Explanation:
The chemical equation for this decomposition of ammonia is
[tex]2 NH_3[/tex] ↔ [tex]N_2 + 3 H_2[/tex]
The initial concentration of ammonia is mathematically represented a
[tex][NH_3] = \frac{n_1}{V_1} = \frac{29}{75}[/tex]
[tex][NH_3] = 0.387 \ M[/tex]
The initial concentration of nitrogen gas is mathematically represented a
[tex][N_2] = \frac{n_2}{V_2}[/tex]
[tex][N_2] = 0.173 \ M[/tex]
So looking at the equation
Initially (Before reaction)
[tex]NH_3 = 0.387 \ M[/tex]
[tex]N_2 = 0 \ M[/tex]
[tex]H_2 = 0 \ M[/tex]
During reaction(this is gotten from the reaction equation )
[tex]NH_3 = -2 x[/tex](this implies that it losses two moles of concentration )
[tex]N_2 = + x[/tex] (this implies that it gains 1 moles)
[tex]H_2 = +3 x[/tex](this implies that it gains 3 moles)
Note : x denotes concentration
At equilibrium
[tex]NH_3 = 0.387 -2x[/tex]
[tex]N_2 = x[/tex]
[tex]H_2 = 3 x[/tex]
Now since
[tex][NH_3] = 0.387 \ M[/tex]
[tex]x= 0.387 \ M[/tex]
[tex]H_2 = 3 * 0.173[/tex]
[tex]H_2 = 0.519 \ M[/tex]
[tex]NH_3 = 0.387 -2(0.173)[/tex]
[tex]NH_3 = 0.041 \ M[/tex]
Now the equilibrium constant is
[tex]K_c = \frac{[N_2][H_2]^3}{[NH_3]^2}[/tex]
substituting values
[tex]K_c = \frac{(0.173) (0.519)^3}{(0.041)^2}[/tex]
[tex]K_c = 14.39[/tex]
Which of the following structures in the human body has the highest level of organization
Answer:
The brain
Explanation:
With all those instructions the body recqures to respond to it must be so
Hope it helps
A sample of helium has a volume of 325 mL and a pressure of 655 mmHg. What will be the pressure, in mmHg, if the sample of helium is compressed to 125 mL (T, n constant)? (Show calculations.)
Answer:
1703 mmHg
Explanation:
Volume and pressure are presumed to be inversely proportional. Hence a change in volume by a factor of 125/325 = 5/13 is expected to change the pressure by a factor of 13/5:
(13/5)(655 mmHg) = 1703 mmHg
What is the atomic mass of AlNO2?
Answer:
I am not sure, but I think this is the answer 72.987 g/mol
which element causes burning when me mix it with oxygen
Answer:
Hydrogen peroxide is ans
Which best describes thermal energy? It is the difference between internal energies of two or more substances. It is the sum of internal energies of two or more substances. It is the portion of internal energy that can be transferred from one substance to another. It is the portion of potential energy that can be transferred from one substance to another.
Answer:
It is the portion of internal energy that can be transferred from one substance to another.
Thermal energy is the portion of internal energy that can be transferred from one substance to another.
What is thermal energy?Thermal energy is the energy an object posses which is as a result of particles movement within it.
It is also the internal energy system in a state of thermodynamic equilibrium which is as a result of its temperature. Thermal energy cannot be concert to useful work easily.
Therefore, thermal energy is the portion of internal energy that can be transferred from one substance to another.
Learn more about thermal energy from the link below.
https://brainly.com/question/19666326
if 196L of air at 1 atm is compressed to 2600mL,what is the new temperature?
Answer:
Around 3.62 degrees kelvin
Explanation:
Assuming this is at STP:
The first step is to convert 2600mL to liters. There are 1000 milliliters in a liter, meaning that this is equal to 2.6L.
Now:
[tex]\dfrac{P_1V_1}{T_1}=\dfrac{P_2V_2}{T_2}\\\\\\\dfrac{196(1)}{273}=\dfrac{2.6(1)}{T_2} \\\\\\T_2\approx 3.62K[/tex]
Hope this helps!
Give the IUPAC name for the following compound
Answer:
3–bromo–5–chloro–4–methylhexane.
Explanation:
To name the compound given in the question, the following must be observed:
1. Locate the longest continuous carbon chain. This gives the parent name of the compound. In this case, the longest chain is carbon 6 i.e Hexane.
2. Identify the substituents attached. In this case the substituents attached are:
a. Chloro i.e Cl.
b. Bromo ie Br.
c. Methyl i.e CH3.
3. Give the substituents the lowest possible count alphabetically. Bromo comes before Chloro alphabetically, so we shall consider bromo first. Their positions are given below:
Bromo i.e Br at carbon 3
Chloro i.e Cl is at carbon 5
Methyl i.e CH3 is at carbon 4
4. Combine the above to get the name of the compound.
Therefore, the name of the compound is:
3–bromo–5–chloro–4–methylhexane.
