Analyze the effectiveness of binary similarity techniques for identifying compounds in untargeted metabolomics.
What is mass spectrometry metabolomics?
Many thousands of metabolite characteristics can be simultaneously detected and quantified using mass spectrometry-based metabolomics methods. However, because of the metabolome's chemical complexity and wide dynamic range, compound identification and accurate quantification are far more difficult.
Many thousands of metabolite characteristics can be concurrently detected and quantified using metabolomics technologies based on mass spectrometry. Due to the metabolome's chemical complexity and dynamic range, molecule identification and accurate quantification are, nonetheless, extremely challenging tasks.
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How many moles of hydrogen are present in a 43.50 ml sample at 25.5 degrees celsius and 772.8 torr?
moles of hydrogen present in a 43.50 ml sample at 25.5 degrees celsius and 772.8 torr are 0.0017
Mole is the name of a common scientific unit used to measure huge amounts of very small objects, such as atoms, molecules, or other specific particles.The principles governing ideal gases are known as ideal gas laws and were developed as a result of Boyle's observational research.The equation of state for a hypothetical ideal gas is known as the ideal gas law. Although it has several drawbacks, it is a good approximation of the behaviour of numerous gases under various circumstances.PV = nRTThe combination of a gas, pressure and volume has a constant relationship with the sum of its moles, temperature, and the universal gas constant.
This problem can be solved by ideal gas law
PV=nRT
P = pressure, 772.8torr × (1atm/ 760 torr)= 1.01 atm
V = volume, 43.50mL (1L/1000mL)= 0.0435L
T = temperature, 25 deg celcius or 273 +25.5= 298.5K
R = 0.0821 (L*atm/K*mol) (constant)
We have to find out n
n= PV/RT
n= (1.01atm)(0.0435L) / (0.0821 L*atm/K*mol) (298.5K)
n= 0.0439 / 24.5
n = 0.0017
Therefore, no of moles of hydrogen are 0.0017.
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identify the conjugate base for each acid. conjugate base of h3po4 : conjugate base of hs− : conjugate base of nh 4
The conjugate base of the acid Nh4+ is ammonia NH3.
What is conjugate base?
A conjugate base is the base member, X-, of two compounds that convert into one another by acquiring or losing a proton, according to a more comprehensive definition. In a chemical process, the conjugate base has the capacity to either gain or absorb a proton.
The conjugate base's formula is the acid's formula less one hydrogen. The base that reacts changes into its conjugate acid. The conjugate acid's formula is the base's formula plus one hydrogen ion.
Because it gives an H+ ion to the water, NH+4 is the acid. After that, it turns into ammonia (NH3), which is the conjugate base of NH+4.
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When doing integrated rate law calculations for second order reactions, we are assuming a rate law that resembles:______.
The rate of such a reaction can be written either as r=AB OR r=A2
Since the, second order reactions can be of two types described below, rate can be given by
r=A×By
It is a chemical reaction in which rate of reaction is proportional to the concentration of each of two reacting molecules.
How do you demonstrate that a reaction is second order?Initial Speed (M/s)
Determine the order of the reaction and the rate constant. If the plot of reactant concentration versus time is not linear but the plot of 1/reaction concentration versus time is linear, the reaction is of second order.SECOND ORDER REACTIONS
Second order reactions are chemical reactions in which the sum of exponents in the corresponding rate law of the chemical reaction equals two. Nitrogen dioxide decomposes into nitrogen monoxide and an oxygen molecule as an example of a second order reaction.Second-order reactions can also occur when the reactants are identical and form a product. Many reactions occur, including nitrogen dioxide decomposition, alkaline hydrolysis of ethyl acetate, hydrogen iodide decomposition, and the formation of double-stranded DNA from two strands.To learn more about SECOND ORDER REACTIONS refer to
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Solve for b.
a(b+1)=-c
when ethane burns in air to form carbon dioxide and water ,heat energy is released. Explain why energy is released
Energy is released because it is a combustion reaction.
Combustion reaction -
Hydrocarbon bonds are broken during combustion events, and more energy is always released during the formation of water and carbon dioxide bonds than was consumed to break the initial hydrocarbon bonds. Burning materials that are primarily made of hydrocarbons produces energy because of this. This is an exothermic reaction.
2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O + Heat
(ethane)
In the process of burning, or combustion, the reactant takes up oxygen and oxidizes it, releasing energy in the form of heat and light. It happens quickly. Along with the energy created during burning, carbon dioxide and water vapor are also produced.
Hence heat and light which are forms of energy are released during combustion reaction.
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Draw a typical hydrogen bond which might be formed for any you specify. a. chlorobenzene b. 1-butanol c. hexane d. ethyl alcohol
1- butanol and (d) ethyl alcohol.
What is a hydrogen bond?Not a covalent link to a hydrogen atom, hydrogen bonding is an unique kind of dipole-dipole interaction between molecules. It comes about as a result of the attraction between two extremely electronegative atoms, such as N, O, or F, and a hydrogen atom that is covalently bound to one of them.Individual water molecules are drawn to one another as a result of the polarity of water. One water molecule's positively charged hydrogen side is drawn to the negatively charged oxygen side of another water molecule nearby. It is known as a hydrogen bond to describe this attraction.A great example of a hydrogen bond is water. Instead of being between the two hydrogen atoms, the connection is between the oxygen atoms in two different water molecules (a common misconception).1- butanol and (d) ethyl alcohol.
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GIVING BRAINLIEST IF YOU HELP!!
An acid can react with a metal hydroxide to form a salt and water. Name the salt formed when sodium hydroxide reacts with ethanoic acid.
Answer: sodium ethanoate
Explanation: I believe that this is correct
Electrochemical forces: if the sum of chemical and electrical driving forces is stronger, then it ____ pushes potassium out of cell rather than into the cell
Potassium will be forced out of the cell rather than into it if the combined strength of the chemical and electrical driving forces is greater.
The electrical potential gradient across the cell membrane and the concentration gradient of the permeant ion across the membrane together make up the net electrochemical driving force. The net driving force can be altered by changing either one. The potential difference across the cell membrane is known as the membrane potential of a cell, which is calculated as the inside potential minus the outside. It happens as a result of the cell membrane's ability to separate charges.
A cell's electromotive force (EMF) The highest potential difference between any two electrodes in a cell is known as the EMF.
Electrochemical forces: If the combined strength of the chemical and electrical driving forces is greater, potassium will be pushed out of the cell rather than into it.
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When a reaction is properly refluxing, where should you see the vapors from the heated mixture? select one:
Vapours should be contained to the reaction flask.
What is properly refluxing?
Reflux is the process of heating a chemical reaction for a predetermined period of time while steadily employing a condenser to cool the resulting vapour back into liquid form. The condensation of the vapours created above the reaction results in their constant return to the flask as a condensate.
Therefore,
When a reaction is properly refluxing, where should you see the vapors from the heated mixture
Vapours should be contained to the reaction flask.
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a piece of sulfur weighs 227 g. when it was submerged in a graduated cylinder containing 50 ml of water, the level rose to 150 ml. what is the density (g/ml) of the sulfur?
The density is = 2.27 g/ml.
A certain object's mass in relation to its volume is measured by its density. High density is a term used to describe materials that are exceedingly compact and have a high mass.
What is density ?A substance's density is defined as its mass per unit of volume. Density is most frequently represented by the symbol, however Latin letter D may also be used. Mass divided by volume is the definition of density in mathematics:
row = m/V
where is the density, m is the mass, and V is the volume.
Given in the question:
Mass of piece of sulfur= 227g
The volume of water that has been disoplaced= (150-50)mL =100mL
We can find the density by:
Density = Mass/Volume
Density = 227/100
Density = 2.27 g/ml
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Calculate the final ph of a solution made by the addition of 10 ml of a 0.5 m naoh solution to 500 ml of a 0.4 m ha originally at ph = 5.0 (pka = 5.0) neglect the volume change.
The final pH of a solution is 5.02 made by the addition of 10 ml of a 0.5 m NaOH solution to 500 ml.
What is pH?
The primary pH standard values are calculated using a concentration cell with transference, by measuring the potential difference between a hydrogen electrode and a standard electrode such as the silver chloride electrode. The pH scale is traceable to a set of standard solutions whose pH is established by international agreement. With the use of a glass electrode, a pH meter, or a color-changing indicator, the pH of aqueous solutions can be determined. In chemistry, agronomy, medicine, water treatment, and many other fields, pH measurements are crucial.
A scale called pH is used in chemistry to describe how basic or acidic an aqueous solution is. Lower pH values are recorded for acidic solutions (solutions with higher H+ ion concentrations) than for basic or alkaline solutions.
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What is the mass of 1.00 mole of an unknown compound with the formula xy if the molecular weight of x is 35.67 g and the molecular weight of y is 40.59 g?
The mass of one mole of this unknown compound 'XY' is 76.26gm.
Given here, the 1 mol of unknown compund 'XY' and mass of X and Y are 35.67gm and 40.59 gm respectively.
Molar mass of XY = molar mass of X + molar mass of Y=35.67gm + 40.59 gm = 76.26gm.
We can find given mass of 'XY' compound by formula,
Mole = Given mass/Molar mass
1= Given mass /molar mass
Given mass = molar mass.
Given mass = 76.26gm.
So, the given mass of XY is equals to 76.26gm.
Mole is defined as the unit of amount of substance. The quantity of amount of substance is measured in mole as 1mol contain exactly 6.023×1023 particles or entities. Mole is calculated by the ratio of the given mass and the molecular mass of the compound.
The relation of mole and molarity is given by the formula, Molarity is equals to no. of moles of solute divided by the solution in litres. S.I unit of molarity is moles per litre.
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in a liquid–liquid extraction, a layer can form between the aqueous and organic layers if the separatory funnel is shaken too vigorously. select the name of this layer. carbonation a gas–liquid interface an emulsion a supercritical fluid
Liquid - Liquid Extraction - It a separation process comprising of the movement of a solute from one solvent to another, the two solvents being not mixable or partially mixable with each other.
Also known as solvent extraction
Organic layer is found to be at the bottom (more dense as compare to water) and aqueous layer found on the top (organic layer less dense as compared to water) in the given liquid liquid extraction.
To find which layer in we can easily add distilled water to the funnel. Whatever layer increases in size must be the aqueous layer and the other is the organic layer.
We can also do the water drop test regarding the same.
Supercritical fluid manages all the different parameters such as temperature, pressure etc.
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what is the arrow pointing to? a solution of different molecules. some of them consist of two small atoms attached to a bigger one. some are negatively charged, and consist of one big atom attached to a small one. there are also small positively charged atoms, which are pointed at by an arrow. what is the arrow pointing to? a solution of different molecules. some of them consist of two small atoms attached to a bigger one. some are negatively charged, and consist of one big atom attached to a small one. there are also small positively charged atoms, which are pointed at by an arrow. electron hydroxide ion hydronium ion water molecule hydrogen ion
Some of them consist of two small atoms attached to a bigger one. Some are negatively charged, and consist of one big atom attached to the small one. The arrow is pointing to a hydrogen ion.
Option A is correct
What is a hydrogen ion? All hydrogen ions and their isotopes must be referred to as hydrogen ions, according to IUPAC,A hydrogen atom loses or gains an electron, leading to the formation of a hydrogen ion. Only when it is in a gaseous state or a condition that is almost particle-free can a positively charged hydrogen ion (or proton) be observed separately because it can easily combine with other particles.A hydrogen atom is made up of a single electron and a nucleus with a charge of 1. That indicates the only positively charged ion which is possible to have charge +1. it is represented as H+.
The hydrogen ion is the only particle that is an atom and also carry a positive charge, i.e., a hydrogen ion is a positively charged atom.
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Question is in complete , missing part is given below :
The figure shows a solution of different molecules. Some of them consist of two small atoms attached to a bigger one. Some are negatively charged, and consist of one big atom attached to the small one. There are also small positively charged atoms, which are pointed by an arrow.
A. hydrogen ion
B. hydronium ion
C. electron
D. hydroxide ion
E. water molecule
suppose that an element has two isotopes. the average atomic mass of the element is 48.184 u48.184 u . one isotope has a mass of 42.450 u42.450 u and an abundance of 35.385.38% . calculate the mass of the second isotope.
The mass of the second isotope is 49.08 u.
Average atomic mass is 45.737 u, while the abundance of isotope 1 is 40.149 u.
? isotope 2?
Process
1.- Determine the isotope 2 abundance: abundance isotope 1 plus abundance isotope 2 equals 100%
100 = 37.46 + abundance isotope 2
Amount isotope 2 equals 100 - 37.46 Amount isotope 2 equals 62.54
2.- Determine the mass of isotope 2. Average atomic mass = (abundance x mass isotope 1) + (abundance x mass isotope 2) 45.737 = (0.3746 x 40.149) + (62.54 x mass isotope 2) Mass isotope 2 = [45.737 - (0.3746 x 40.149)]
62.54 mass isotope 2 equals [45.737 - 15.0398] 62.54 mass isotope 2 equals 30.6972 62.54 mass isotope 2 equals 0.4908 x 100 mass isotope 2 equals 49.08 u
What is an isotope ?Isotopes are members of the same family of elements as that element but have varying numbers of neutrons. The Periodic Table's atomic number of an element is determined by the number of protons it contains. The atomic number 6 of carbon, for instance, has six protons.
Any of two or more types of chemical element atoms that have the same atomic number and essentially the same chemical behavior, but different atomic masses or mass numbers and different physical qualities
Uranium-235, uranium-238, tritium (hydrogen-3), chlorine-36, and carbon-14 are a few examples of radioactive isotopes. There are certain isotopes that have exceptionally lengthy half-lives (in the order of hundreds of millions of years). Stable nuclides or stable isotopes are the terms used to describe these isotopes.
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An irregular object has a mass of 125.5 grams. A graduated cylinder is filled to 61.0 mL and the irregular object is dropped in and it rises to 71.0 mL. Find the density.
Explanation:
density=mass÷volume
volume of irregular object= 71-61= 10 mL
density=125.5÷10
density= 12.55g/mL
You take out your best silver spoons and
notice that they
are very dull and have
some black spots.
Is it a chemical change or physical and why?
Assuming each measurement can be made to /- 0.05 ml, what is the percentage error in using a buret to deliver 40.0 ml of solution into an erlenmeyer flask?
The percentage error in using a buret to deliver 40.0 ml of solution into an erlenmeyer flask is 0.13%.
Given,
Theoretical value = 40ml
Experimental value = (40-0.05)ml = 39.95ml
%Error = |Experimental value - Theoretical value| / |Theoretical value| x 100
= |39.95 - 40| / |40| x 100
= 0.0499999 / 40 x 100
=0.00125 x 100
=0.125.
%Error = 0.13.
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a certain ore is 27.9'.9% nickel by mass. how many kilograms of this ore would you need to dig up to have 85.0 g85.0 g of nickel?
A certain ore is 27.9'.9% nickel by mass. - 28544692. kilograms of this ore would you need to dig up to have 85.0 g85.0 g of nickel.
What is nickel ?Chemical element nickel has the symbol Ni and atomic number 28. It is a beautiful silvery-white metal with a faint golden hue. The transition metal nickel is hard and ductile. Although bigger particles of pure nickel are slow to react with air under typical conditions because an oxide layer builds on the surface and limits further corrosion, pure nickel that has been powdered to increase reactive surface area exhibits high chemical activity (passivation).
Yet pure native nickel is only occasionally found in the crust of the Earth, typically in ultramafic rocks and the interiors of bigger nickel-iron meteorites that were not exposed to oxygen during their time outside the Earth's atmosphere.
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1.15(a) a gas at 250 k and 15 atm has a molar volume 12 per cent smaller than that calculated from the perfect gas law. calculate (a) the compression factor under these conditions and (b) the molar volume of the gas. which are dominating in the sample, the attractive or the repulsive forces?
(a)The gas has a compressibility factor of 0.88 and a molar volume of 1.204 litre mol-1.
(b)The gas has a 1.12 compressibility factor and occupies a 2.682 litre mol^-1 molar volume.
What is compressibility factor?
The compressibility factor (Z), often referred to as the compression factor or the gas deviation factor, is a term used in thermodynamics to describe how a real gas deviates from the behavior of an ideal gas. The molar volume ratio of a gas to an ideal gas at the same temperature and pressure is the simplest way to describe it.
(a) compressibility factor (Z)= Vm/Vmo
where Vm is the molar volume and molar volume molar volume Vmo
putting the values we get :
Vm = 0.88 Vmo
Z= 0.88
therefore Vm = 0.88 x 0.0821 x 250 /15 litre mol^-1
(b) similarly we can calculate
Vm = Vmo + 0.12 Vmo
Therefore, after putting the values Z= 1.12
Vm= 1.12 x 0.0821 x 350 /12 litre mol^-1
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The _______ gland releases the hormone adrenaline.
Answer:
adrenal
Explanation:
The adrenal glands. (I kid you not)
Is it possible to prepare (s)-2-bromo-3-methylbutane in high yield by halogenation of an alkane?
Which phenomenon is most likely due to the high specific heat capacity of water?
Due to the large specific heat capacity of water, Santa Monica Bay, off the coast of Los Angeles, experiences less seasonal temperature variation than the surrounding air.
What is specific heat capacity?
The amount of heat required to increase a substance's temperature by one degree Celsius (°C) in one gram is known as specific heat. Water has a high specific heat, which means that heating it up requires more energy than heating up other substances.
Specific heat capacity (symbol: c) in SI units is the quantity of heat in joules needed to elevate 1 gram of a substance by 1 Kelvin. J/kgK is another way to put it. It is also possible to express a specific heat capacity in terms of calories per gram of temperature in Celsius.
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identify each described physical separation technique. a liquid is carefully poured out, leaving the solid behind in the container
A liquid is gently poured out, leaving the solid in the container, in a process known as decantation.
What is decantation?
The process of decanting is used to separate mixtures of incompatible liquids or liquid and solid mixtures, such as suspensions. The liquid that is closer to the top of the container—the less dense of the two liquids or the liquid from which the precipitate or sediment has settled out—is poured off, leaving the other component or the denser liquid of the mixture behind.
During the separation of two immiscible liquids, an imperfect separation is observed. Decantation, to put it simply, is the process of shifting the top layer of immiscible materials to another container in order to separate the contents.
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What is true about these atoms and molecules?
O All of these are molecules
O B and Care atoms; A, D and E are molecules
O A, D and E are atoms; B and C are molecules
O A and D are atoms; B, C and are molecules.
Answer:
Tbh it doesn't look right because A D are atoms B E C are molecules.
Explanation:
The reason I think that is because E is the molecule of elements while B and C are molecules of compounds can you maybe recheck?
when one molecule of sucrose is burned with oxygen to make carbon dioxide and water, how many carbon dioxides are made? hint, carbon dioxide is co2.
One molecule of sucrose is burned with oxygen to make carbon dioxide and water.
What is sucrose?
The components of the disaccharide sugar sucrose are glucose and fructose. It is produced naturally by plants and is the main component of white sugar. C12H22O11 is the chemical formula for it.
To extract and refine sucrose for human use, either sugarcane or sugar beet are employed. Crushing the cane creates raw sugar, which is subsequently delivered to other sectors to be refined into pure sucrose. Sugar mills are usually located in tropical regions near to sugarcane plantations.
C12H22O11 + 12O2 = 12CO2 + 11H2O
When one molecule of sucrose is burnt, we get 12 carbon dioxide molecules.
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The smaller triangle is a pre-image of the bigger triangle. The center of dilation is (2, −1).
What is the scale factor used to create the dilation?
By using rule for dilation, scale factor used to create the bigger triangle will be (-2) when the small triangle is a pre- image.
Coordinates of a point (x, y) dilated by a scale factor 'k' about a point (a, b) is given by,
Coordinates of the image point → [k(x - a) + a, k(y - a) + b]
Point of dilation → (2, -1)
Vertices of the smaller triangle (preimage) → (-1, -1), (2, 2) and (2, -1)
Corresponding vertices of the bigger or dilated triangle → (8, -1), (2, -7) and (2, -1)
By the rule of translation,
Image of vertex (-1, -1) → [k(-1 - 2) + 2, k(-1 + 1) - 1]
→ [(-3k + 2), -1]
image of the point (-1, -1) is (8, -1).
Therefore, (-3k + 2) = 8
-3k = 8 - 2
k = -2
Hence, scale factor used to create the dilation will be (-2).
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The energy flow to the earth from sunlight is about 1.4 kw>m2 . (a) find the maximum values of the electric and magnetic fields for a si- nusoidal wav
The maximum values of the electric and magnetic fields is 3.42*[tex]10^{-6}[/tex] T.
What is the electric and magnetic field?Electric fields arise from the electric charges and changing magnetic fields.
An electric charge, or collection of the charges, will have an associated electric field. Any charged object placed in this field will experience an electrostatic force as field interacts with the charge of the object. Field lines represent force a positively charged particle would experience if it were in the field at that point.
A changing magnetic field can also cause the electric charges to move. This phenomenon is commonly used in the electric generators to induce electric currents in wires. The induced current can be increased by causing the larger changes in the magnetic field or by coiling the wire so that more wire is affected by the changing magnetic field.
Magnetic fields arise from the permanent magnets and electric charges in motion.
Magnets can occur naturally (such as the Earth’s magnetic field), or they can be made by magnetizing the ferromagnetic materials.
Intensity I = 1.4*[tex]10^{3}[/tex] w/[tex]m^{2}[/tex]
Total Energy density [tex]U_{avg}[/tex] = [tex]\frac{1}{2} E_{o}E_{o} ^{2}[/tex]
a) energy density = I/C
Therefore, 1/2 [tex]E_{o}E_{o}^{2}[/tex] = I/C
1/2 * 8.85 * [tex]10^{-12}[/tex] * [tex]E_{o}^{2}[/tex] = 1400/(3*[tex]10^{8}[/tex])
[tex]E_{o} ^{2}[/tex] = 105.46*[tex]10^{4}[/tex]
[tex]E_{o}[/tex] = 10.27*[tex]10^{2}[/tex] N/C
[tex]B_{o}[/tex] = [tex]\frac{E_{o} }{C}[/tex] = (10.27*[tex]10^{2}[/tex])/ (3*[tex]10^{8}[/tex]) = 3.42*[tex]10^{-6}[/tex] T
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Elements on the LEFT side of the periodic table will
most likely form:
Positive ions
None of these
Choose the best description for prokaryotic cell.
has a nucleus; found in multicellular organisms
has no nucleus; found in unicellular organisms
has no nucleus; found in multicellular organisms
has a nucleus; found in unicellular organisms
Answer:
has no nucleus; found in unicellular organisms
Explanation:
Hope It Helps
Sorry If I'm Wrong
Answer: Has no nucleus found in unicellular organisms
Explanation:
Prokaryotic cells are primitive cells found in lower organisms. Prokaryotic cells do not have a true cell.
A true nucleus lacks an envelope which contains the nuclear materials.
Most of the organelles lacks membrane bound organelles.
The true nucleus is lacking in prokaryotes.
Eukaryotic cells have true nucleus.