Distillation is a technique in which substances are separated based on their what

Answers

Answer 1

Answer:

It is based on the boiling point or volatility of its components.

Explanation:

because Distillation separates liquid from solid.


Related Questions

If 0.050 mol hydrochloric acid (HCl) is mixed with 0.050 mol of sodium hydroxide (NaOH) in a "coffee cup" calorimeter, calculate the temperature change of 47.0 g of the resulting solution if the specific heat of the solution is 1.00 cal/g·°C and the quantity of heat released by the reaction is 8.8 × 102 cal.

Answers

The temperature change of the resulting solution, given that the soluton has a specific heat of 1 cal/g·°C is 18.7 °C

How do I determine the temperature change?

We know that heat released is related to change in temperature according to the following formula:

Q = MCΔT

Where

Q is heatM is the mass C is the specific heat capacityΔT is the temperature change

Using the above formula, the temperature change of the solution can be obtained as follow:

Mass of solution (M) = 47.0 gSpecific heat capacity of silver (C) = 1.00 Cal/g·°CHeat released (Q) = -8.8×10² CalTemperature change (ΔT) = ?

Q = MCΔT

-8.8×10² = 47 × 1 × ΔT

-8.8×10² = 47 × ΔT

Divide both side by 47

ΔT = -8.8×10² / 47

ΔT = -18.7 °C

Thus, the temperature change is 18.7 °C

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When heated, calcium carbonate, CaCO3(s) , decomposes to calcium oxide, CaO(s) , and carbon dioxide, CO2 . Using relevant data from your book's appendices, calculate the heat evolved or consumed when 15.0 g of calcium carbonate are decomposed. answer: kJ

Answers

As per the standard data, the heat evolved during one mole of calcium carbonate decomposes is 177.8 KJ. Thus 15 g or 0.15 moles of calcium carbonate when decomposed will produce 26.67 KJ of heat.

What is reaction enthalpy?

Reaction enthalpy of a substance is the heat evolved or absorbed during a reaction. Reaction enthalpy is negative for an exothermic reaction and positive for an endothermic reaction.

Molar mass of calcium carbonate = 100 g.

no.of moles in 15 g = 15 /100 = 0.15 moles.

One mole or 100 g of calcium carbonate decompose to evolve 177.8 KJ according to the scientific record.

Thus, heat evolved by the decomposition of 0.15 moles is 0.15 × 177.8 KJ = 26.67 KJ.

Hence, the heat evolved during the decomposition of 15 g of calcium carbonate is 26.67 KJ.

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How many grams of hydrogen gas (don't forget it's diatomic) can be produced when 5.45 g of iron reacts with excess HCI? 2Fe(s) + 6HCl(aq) --> 2FeCl3(aq) + 3H2 (g)

Answers

Answer: 0.295g

Explanation: The answer is 0.295g. Normally you would start by checking which of your reactants is the limiting reactant, but since you have excess HCl, you don't need to worry about that. Start by converting grams of iron to moles (done by dividing grams by iron's molar mass).

Next, you convert moles Fe to moles H2 by checking the coefficients in front of Iron and H2. Divide by iron's coefficient and multiply by H2's

Finally, you multiply by the molar mass of H2. To find it, multiply the molar mass of hydrogen by 2.

Easy way to read it:
5.45/44.845 x 3/2 x 2(1.008) = 0.295

You make a stock solution using 17.26 mg of a dye with a molar mass of 225.8 g/mol and you add water until you reach a volume of 500.0 mL. What is the concentration of the dye in the stock solution? Give your answer in all of the units requested (M, mM)

Answers

Answer:

Molar mass of dye = 225.8 g/mol

Mass of dye = 17.26 mg

Volume of stock solution = 500.0 mL

Concentration of dye (M) = (17.26 mg/225.8 g/mol) / (500.0 mL/1000 L) = 0.000769 M

Concentration of dye (mM) = 0.769 mM

According to the molar concentration, the concentration of the dye in the stock solution is 15.04×10⁻³M and 15.04×10⁻⁶mM.

What is molar concentration?

Molar concentration is defined as a measure by which concentration of chemical substances present in a solution are determined. It is defined in particular reference to solute concentration in a solution . Most commonly used unit for molar concentration is moles/liter.

The molar concentration depends on change in volume of the solution which is mainly due to thermal expansion. Molar concentration is calculated by the formula, molar concentration=mass/ molar mass ×1/volume of solution in liters.

In terms of moles, it's formula is given as molar concentration= number of moles /volume of solution in liters.

Substitution of values in formula gives, M= 0.017/225.8×1/0.5=15.04×10⁻³ M or 15.04×10⁻⁶ mM.

Thus, the concentration of the dye in the stock solution is 15.04×10⁻³M and 15.04×10⁻⁶mM.

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What is the pH of an aqueous solution with a hydrogen ion concentration of [H+]=7.7×10−4 M?

Answers

Answer:

What is the pH of an aqueous solution with a hydrogen ion concentration of [H+]=7.7×10−4 M?

The pH of an aqueous solution with a hydrogen ion concentration of [H+]=7.7×10−4 M is 3.11.

Define inference and explain how it is used to form conclusions.

Answers

Answer:

an inference is an educated answer based on a piece of information you have been given

Explanation:

e.g. they had pigtails in their long blonde hair.

from this we can infer that I am speaking about a girl

Consider these questions about living with nuclear power, and then answer them.

1. Would you live near a nuclear power plant? Explain your response.
2. What kinds of jobs are available at a nuclear power plant?
3. Identify the benefits and risks to someone who is working at a nuclear power plant.
4. How does the presence of a nuclear power plant impact the economy of local communities and the lives of people living nearby?
5. What do you think are some reactions of individuals within the communities that are close to nuclear power plants? Explain why you think they might have these reactions.

Answers

Answer:

Explanation:

1. No, I simply would not feel safe.

2. Power plant manager

3. exposure to chemicals

Complete the table. Then explain how wavelength and frequency are mathematically related.

Answers

The wavelength is same.

What is wavelength?

Wavelength can be defined as the distance between two successive by throughs of a wave.

The question wants you to determine the energy that is the incoming photon by the  must have in order to the accept the electron that melted  it tob the jump to 2 to 1.

A good starting point here will be to calculate the energy of to the photon emitted when the electron falls from  1 to 2

by applying the Rydberg equation.

1/π = R

λ

 si the wavelength of the emittted photon R

 is the Rydberg constant, equal to 1.907.

This means that you haveλ=

4.10

So, you know that when an electron falls from the

to  

a photon of wavelength by the

410 nm

 is emitted. This implies by  that in order to the for the electron by jump to  the 2 to 1 .

 it must absorb a photon of the same wavelength.

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A gas occupying 50.0 ml volume in a confined space at 20.0 dc at 50.0 kpa is heated to 40.0 dc. What is the pressure exerted by the gas in the container?

Answers

Answer:The pressure exerted by the gas is 100kPa

Explanation:Let's apply the Charles Gay Lussac law, to solve the question.

At constant volume, the pressure varies proportionally with the temperature.

P initial / T° initial = P final / T° final

50kPa / 20°C = P final / 40°C

Temperature has increased the double, so the pressure will be increased, the double too.

100 kPa

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a) Are Albumin compact, globular proteins?​

Answers

[tex]{ \blue{ \sf{Albumin}}}[/tex] is a soluble and globular monomeric protein encoded by chromosome 4 that comprises about half of the protein found in blood serum. It functions as a carrier protein for steroids, fatty acids, and thyroid hormones as well as stabilizing extracellular fluid volume.

Use Lewis structures to determine which two of the following are unstable: (a) SF2; (b) SF3; (c) SF4; (d) SF5; (e) SF6.

Answers

According to the Lewis structures, SF₂ is unstable as it has 2 lone pairs of electrons.

What are Lewis structures?

Lewis  structures are also called as electron dot structures and can be drawn if the molecular formula of a compound is known. It provides information regarding the nature of bond and the position of atoms .

They are also capable of exhibiting the lone pair if any present in a molecule or compound.Lewis defined a base to be an electron pair donor and an acid to be an electron pair acceptor.

They are capable of reflecting electronic structure of elements and even the pairing of electrons . In the diagram, each dot represents an electron while a pair of dots represent a bond between the atoms.

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a student is performing experiments on a particular substance. which statement is a observation of a chemical property of the substance?

Answers

Answer:

a

Explanation:

bc i think it is and pls i wany to have ajebehhe

Answer:

if it burns

Explanation:

4. Which of the following properties of fluorine is a physical property?
A.Fluorine gas is flammable.
B.All metals corrode in the presence of fluorine.
C.Fluorine gas is poisonous.
D.The liquid phase of fluorine is pale yellow.

Answers

Answer:

A

Explanation:

Fluorine is a REACTIVE nonflammable gas or liquid which will enhance combustion of other materials.

Calculate the standard enthalpy change for the reaction

2A+B⇌2C+2D 

Use the following data:

Substance ΔH∘f
( kJ/mol)
A -231
B -409
C 177
D -515
Express your answer to three significant figures and include the appropriate units.

Answers

The standard enthalpy change for the reaction 2A + B ⇌ 2C + 2D   is 195 kJ/mol.

What is the enthalpy of a reaction?

The enthalpy of a reaction is a measure of the heat changes that occur when reactants form a product in a given reaction.

The enthalpy change of a reaction can be calculated using the formula given below:

Enthalpy of reaction = sum of enthalpies of the products  - sum of enthalpies of the reactants

Considering the given reaction: 2A + B ⇌ 2C + 2D  

Enthalpy of reaction = (2 * C + 2 * D) - (2 * A + B)

Enthalpy of reaction = {[2 * 177 + 2 * (-515)] - [2 * (-231) + (-409)]}

Enthalpy of reaction = 195 kJ/mol

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This hydrocarbon is incomplete. Draw the hydrogen atoms and the bonds connecting them to carbon atoms such that each carbon atom has four bonds. Then record the number of hydrogen atoms you drew using a text box.

Answers

Answer:

H/Hydrogen atoms = 12

reason:

no. of carbon=5

so it'll be C5H12

Calculate the kinetic energy of a 150 g baseball moving at a speed of 36. m/s (81 mph).

Answers

Answer:

KE=1\2mv2

KE=0.5 *0.15*(36)2

97.2j

what is the name of ch3cooc2h5​

Answers

Answer:

ethyl ethanoate

Explanation:

it helps you

Ethyl acetate is the name

The following image shows a man running with a training parachute. The man is pushing himself forward with a force of 30 newtons. The net force on the man is 10 newtons forward. What is the parachute doing?

It is pushing the man forward with 10 newtons of force.

It is reducing the force by increasing the runner's mass.

It is making the runner travel at a constant speed.

It is pulling the man backward with 20 newtons of force.****

Answers

The net force on the man is 10 newtons forward. The parachute is pushing the man forward with 10 newtons of force. Therefore, option A is correct.

What is net force ?

The vector sum of the forces exerted on a particle or object is known as the net force. The original forces' impact on the motion of the particle is replaced by the net force, which is a single force.

In accordance with Newton's second rule of motion, it causes the particle to accelerate at a rate equal to the sum of all those actual forces.

The vector sum of all forces exerted on an object is known as the net force. The net force acting on an object is zero when it is in equilibrium, whether it is at rest or moving at a constant speed. Only when all of a vector's components are zero can a vector have a magnitude of zero.

Thus, option A is correct.

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Answer: A

Explanation:

Use the bond energies in the table to estimate the enthalpy of reaction for the formation of sulfur tetrafluoride monoxide.

Answers

The enthalpy of reaction for the formation of sulfur tetrafluoride monoxide is 16 kJ/mol.

What is the enthalpy of a reaction?

The enthalpy of a reaction measures the sum total of the heat that is absorbed or liberated in a given reaction when reactants react to form products.

The enthalpy change of a reaction can be calculated using the formula given below:

Enthalpy of reaction = sum of bond energies of the products  - sum of bond energies of the reactants

The equation of the given reaction is as follows:

SF₄ + ¹/₂ O₂-----> SF₄O

Enthalpy of reaction = (4 * S-F + S-O) - (4 * S-F + ¹/₂ * O-O)

Enthalpy of reaction = (4 * 310 + 265) -  (4 * 310 + /₂ * 498)

Enthalpy of reaction = 16 kJ/mol

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A gas mixture was prepared to contain 50% by mass of O, and Ne. When the total pressure of the mixture is 1.50 atm, what is the partial pressure of O₂?​

Answers

The partial pressure of oxygen is the product of its mole fraction and the total pressure. Partial pressure of O₂ here, is 0.82 atm.

What is partial pressure?

Partial pressure of an individual gas in a mixture of gases is its contribution to the total pressure of the gas mixture. According to Dalton's law of partial pressures, the total pressure of the mixture is the sum of partial pressures of the individual gases.

The partial pressure of the individual gases will be the product of the mole fraction and total pressure.

mass of oxygen = 16 g/mol

number of moles in 50 g = 50 /16 = 3.125 moles.

mass of neon = 20 g/mol

moles in 50 g =  50 / 20 = 2.5 moles.

Mole fraction of oxygen =  3.125/ (3.125 + 2.5) = 0.55.

Partial pressure = mole fraction × total pressure

                           = 0.55 × 1.50 atm = 0.82 atm.

Therefore, the partial pressure of O₂ in the mixture is 0.82 atm.

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According to molecular orbital theory, which species in the following list are paramagnetic: H2+, C22–, and N22–?

A. H2+ and N22-
B. H2+, C22-, and N22-
C. H2+ and C22-
D. C22-, and N22-
E. H2+ only

Answers

D. Is the correct answer I believe

(e) What type of reaction takes place when zinc reacts with copper oxide? Tick one box. Combustion
Crystallisation
Displacement
Neutralisation oxide​

Answers

To solve such this we must know the concept of displacement reaction. Therefore, the correct option is option C that is displacement reaction.

What is chemical reaction?

Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.

when zinc reacts with copper oxide then zinc displace copper from copper oxide as zinc is more reactive than copper on the reactivity series. So, copper is displaced by zinc.

Therefore, the correct option is option C that is displacement reaction.

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If the density of an ideal gas at STP is found to be 0.716 g/L, what is its molar mass?

Answers

Answer:

GL

Explanation:

How many moles of lithium metal react to yield 5.00 mol of hydrogen
gas?
_Li(s) + H₂O(0)→ _LiOH(aq) + _H₂(g)
O none of the above
O 20.0 mol
O 2.50 mol
O 10.0 mol
O 5.00 mol

Answers

According to stoichiometry and balanced chemical equation  10 moles of lithium metal react to yield 5.00 mole of hydrogen gas.

What is stoichiometry?

Stoichiometry is the determination of proportions of elements or compounds in a chemical reaction. The related relations are based on law of conservation of mass and law of combining weights and volumes.

Stoichiometry is used in quantitative analysis for measuring concentrations of substances present in the sample.

In the  balanced chemical equation as 2 moles of lithium produce 1 mole of hydrogen.

∴for 5 moles of hydrogen to be liberated,5×2/1=10 moles of lithium are required.

Thus, 10 moles of lithium are required to react to yield 5 moles of hydrogen gas.

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Suppose you are standardizing a sodium hydroxide solution with KHP

(molar mass=204.2 g/mol) according to the equation

KHP+NaOH⟶H2O+NaKP

You prepare the standard solution from 0.303 g of KHP
in 250.0 mL of water. You then require 9.51 mL of NaOH

solution to complete the titration.

What is the concentration of the NaOH
solution?

Answers

Answer:

Suppose you are standardizing a sodium hydroxide solution with KHP

(molar mass=204.2 g/mol) according to the equation

KHP+NaOH⟶H2O+NaKP

You prepare the standard solution from 0.303 g of KHP

in 250.0 mL of water. You then require 9.51 mL of NaOH

solution to complete the titration.

What is the concentration of the NaOH

solution?

Answer:

The concentration of the NaOH solution can be calculated using the following equation:

Concentration (M) = (Moles of KHP/Volume of NaOH solution) x (Molar mass of KHP/1000)

Concentration (M) = (0.303 g/9.51 mL) x (204.2 g/mol/1000)

Concentration (M) = 0.064 M

How many Grams of ribose (a carbohydrate) must be added to
200 mL of water to prepare a O.IM ribose solution?

Answers

Answer:

3 grams C₅H₁₀O₅

Explanation:

To find the mass of ribose needed to prepare the sample, you need to

(1) convert the volume from mL to L (1,000 mL = 1 L)

(2) calculate the number of moles (M = moles / L)

(3) convert moles to grams (using the molar mass of ribose)

The molecular formula of ribose is C₅H₁₀O₅. It is important to arrange all of the ratios/conversions in a way that allows for the cancellation of units.

(Step 1)

 200 mL C₅H₁₀O₅                   1 L
----------------------------  x  ----------------------  =  0.2 L C₅H₁₀O₅
                                           1,000 mL

(Step 2)

Molarity (M) = moles / volume (L)                 <----- Molarity ratio

0.1 M = moles / 0.2 L                                     <----- Insert values

0.02 = moles                                                  <----- Multiply both sides by 0.2 L

(Step 3)

Atomic Mass (C): 12.011 g/mol

Atomic Mass (H): 1.008 g/mol

Atomic Mass (O): 15.999 g/mol

Molar Mass (C₅H₁₀O₅): 5(12.011 g/mol) + 10(1.008 g/mol) + 5(15.999 g/mol) = 150.13 g/mol

 0.02 moles C₅H₁₀O₅              150.13 g
----------------------------------  x  -------------------  =  3 grams C₅H₁₀O₅
                                                  1 mole

between ethane, ethene and ethyne which is having shortest bond?​

Answers

As you can see the picture, in the three given compounds i.e. ethane, ethene and ethyne, ethyne have shortest bond. Bond length of ethyne is very short when compared to the ethane and ethene. Shorter the bond, bond strength will be more. Hence, our answer is ethyne.

Answer:

ethyne has shortest bond

Elements that are chemically similar to calcium (Ca) can interfere with bodily functions. Which of the following elements could react similar to calcium’s role in bodily functions?

Answers

Elements that are chemically similar to calcium (Ca) can interfere with bodily functions are Beryllium and magnesium.

What is calcium ?

The chemical element calcium has the atomic number 20 and the letter Ca as its symbol. Calcium is an alkaline earth metal that reacts with air to create a black oxide-nitride coating. Its heavier homologues barium and strontium are most similar to it in terms of physical and chemical characteristics.

Calcium reacts when heated with boron, carbon, sulfur, phosphorus, halogens, and hydrogen. Calcium is more expensive and less reactive than sodium, despite being a better reducing agent than the latter.

Thus, Elements that are chemically similar to calcium (Ca) can interfere with bodily functions are Beryllium and magnesium.

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By what factor would the average kinetic energy of the particles be increased if the
temperature a substance was increased from -49C to 287C?

Answers

Average kinetic energy is the average sum of all kinetic energy of all the molecules of gases. Therefore, the new kinetic energy is 48 times the original kinetic energy.

What is kinetic energy?

It is a energy which is possess  by a moving object. It is very difficult to find the correct value of kinetic energy so we find average kinetic energy. Which is very easy to calculate as compared to calculating kinetic energy

Average kinetic energy is directly proportional to temperature. It is not dependent on the type of gases or mass of gases

Mathematically,

K.E=2/3KT

Where,

K= Boltzmann constant

T is the temperature

Gases at higher temperature will have higher average kinetic energy. For every 10 degree rise in temperature, kinetic energy of reaction gets double. There are 24 times 10 between the given temperature  -49C to 287C. So, the new kinetic energy is 48 times the original kinetic energy.

Therefore, the new kinetic energy is 48 times the original kinetic energy.

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A sample of nitrogen dioxide gas occupies 625 cm3 at 70.0 °C and 15.0 psi. What is the final Celsius temperature if the volume is 545 cm3 at 15.0 psi?

Answers

The final temperature of the sample of nitrogen dioxide gas that occupies 625 cm³ at 70.0 °C and 15.0 psi is 299.12K.

How to calculate temperature?

The temperature of a gas can be calculated by using the combined gas law formula as follows:

P₁V₁/T₁ = P₂V₂/T₂

Where;

P₁ = initial pressureV₁ = initial volumeT₁ = initial temperatureP₂ = final pressureV₂ = final volumeT₂ = final temperature

According to this question, a sample of nitrogen dioxide gas occupies 625cm³ at 70.0 °C and 15.0 psi. The final temperature can be calculated as follows:

15 × 625/343 = 15 × 545/T

27.33T = 8175

T = 299.12K

Therefore, 299.12K is the final temperature of the sample of nitrogen dioxide gas.

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