although generally less precise than radiocarbon, thermoluminescence (tl) dating has an advantage over radiocarbon dating: it can date:

According to the given statement The volume of the dry gas at STP is 0.259 L (259 ml).

A gas with an extremely straightforward connection between pressures, volume, and temp called an ideal gas. An ideal gas's volume and pressure are directly inversely correlated with its molecular weight and absolute temperature. Temperature and pressure in such an ideal gas are inversely correlated.

P = 789.8 mmHg = 789.8 torr

V = 256 ml

T = 25 + 273.15 = 298.15 K (temperature in Kelvin)

Having isolated the moles of gas and written the ideal gas law,

n = PV/(RT)

= (1.0382 atm) * (0.256 L) / [(0.0821 L•atm/(mol•K)) * (298.15 K)]

= 0.0111 mol

At STP, an ideal gas has a molar volume of 22.4 L. The molar volume is used as a conversion factor to determine the volume of the dry gas at STP.

P = 1 atm

T = 273.15 K

n = 0.0111 mol

V = nRT/P

= (0.0111 mol) * (0.0821 L•atm/(mol•K)) * (273.15 K) / (1 atm)

= 0.259 L

Therefore, the volume of the dry gas at STP is 0.259 L (259 ml).

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In a liquid state, where they have greater energy, water molecules travel more swiftly and essentially bounce against one another than they do in a solid form. When the liquid cools, potential energy diminishes.

During freezing, a substance's temperature stays constant while the liquid's dissolved particles transform into crystalline solids. Energy escapes during freezing because liquid particles have more energy then particles in a solid. The environment receives this energy's discharge.

Gas molecules are far more energetic and disperse than liquid molecules do. Since warm water has much more energy that cold water, warm water molecules travel more quickly than cold water molecules.

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Answer:

16g

Explanation:

1 mole of O2 = 32 g = 6.022 x 10^23 molecules

3 x 10^23 molecules weights

3 x 10^23 x 32/(6.022 x 10^23)

= 15.94g or 16g

The proper inlet port for the coolant water in a water-cooled West condenser is the bottom port.

A water-cooled West condenser is a device used to cool and condense solvent vapors during the process of heating reactions under reflux. This type of condenser is equipped with two ports for the inlet and outlet of coolant water. It has a glass outer tube and an inner tube made of either glass or PTFE (Polytetrafluoroethylene). The space between the two tubes is where the coolant water flows. This arrangement of tubes creates a space for the vapor to be cooled before it is condensed by the coolant water.

The proper inlet port for the coolant water in a water-cooled West condenser is the bottom port. This is because the coolant water flows from the bottom up towards the top. Therefore, introducing the coolant water into the bottom port will ensure that the water is flowing in the correct direction. In addition, the top port serves as the outlet port for the coolant water, allowing it to flow out of the condenser after it has absorbed the heat from the solvent vapors.

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The type of light that can be broken into its individual wavelengths by a prism is Ultraviolet. The correct answer is Option B.

Ultraviolet (UV) light is a form of electromagnetic radiation that is invisible to the eye. Ultraviolet radiation has a wavelength that is shorter than visible light but longer than X-rays. This is the type of light that can be broken down into its individual wavelengths by a prism.

A prism is a piece of glass or other transparent material with a specific shape that can split white light into its component colors. The process of bending and separating light is known as dispersion. The index of refraction of the glass, as well as the angle of incidence, determines the amount of refraction that occurs.

In conclusion, ultraviolet light is the type of light that can be broken down into its individual wavelengths by a prism.

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The average velocity of sulfur dioxide gas under the same conditions is approximately 303 m/s.

Under the same temperature and pressure conditions, the average velocity of a gas is proportional to the square root of its molar mass. Therefore, we can use the following formula to find the average velocity of sulfur dioxide (SO2) gas:

vSO2 = (MSO2 / MCl2)1/2 × vCl2

where vCl2 is the average velocity of chlorine gas, MSO2 is the molar mass of sulfur dioxide, and MCl2 is the molar mass of chlorine gas.

The molar mass of SO2 is approximately 64 g/mol, and the molar mass of Cl2 is approximately 71 g/mol. Therefore:

vSO2 = (64 g/mol / 71 g/mol)1/2 × 324 m/s

vSO2 = 0.936 × 324 m/s

vSO2 ≈ 303 m/s

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The net chemical equation for the production of hydrogen from propane and water is:

[tex]C_{3}H_{8}+3H_{2}O -- > 4H_{2}+3CO_{2}[/tex]

The reaction between propane and water can be used to produce hydrogen gas. The production of hydrogen gas from propane and water is an important reaction that has several applications. The balanced equation for the production of hydrogen gas from propane and water is given as follows:

[tex]C_{3}H_{8} +3H_{2}O-- > 4H_{2}+3CO_{2}[/tex]

The reaction between propane and water can be catalyzed by several metals such as nickel or platinum. The process is called steam reforming, and it is used to produce large quantities of hydrogen gas. Hydrogen is used as a fuel in fuel cells and combustion engines. It is also used in the production of ammonia and methanol, and as a reducing agent in various chemical processes.

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It is a non-electrolyte is not an attribute of an acid.

What are Acids?

Acids are characterized as materials that can discharge hydrogen particles when they break up in a water-based solution. An acidic solution is one that contains more hydrogen particles, H+ than hydroxide particles, OH-. Acids have a pH value of less than 7.0.

The strength of the acid is determined by the concentration of hydrogen ions, H+.

When acids are mixed with a base, they react to produce a salt and water. Acidic solutions have a sour taste and can dissolve metals. Acids turn blue litmus paper red. Acids are used in numerous industrial applications, such as the production of fertilizers, plastics, and dyes, as well as the production of fuels from oil and gas.

They are employed in numerous chemical reactions and cleaning operations. They are widely used in the food industry as a preservative and to add flavor. They are also utilized in medicine to make supplements and for the treatment of diseases.

Thus, it is a non-electrolyte is not an attribute of an acid.

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16 mL of 0.610 M NaOH solution is required to neutralize 20.0 mL of 0.245 M H2SO4 solution.

Chemical reaction between acid and a base that results in the formation of a salt and water is called neutralization.

2 NaOH+ H₂SO₄ → Na₂SO₄ + 2 H₂O

Number of moles of  H₂SO₄ in 20.0 mL of a 0.245 M solution is: n( H₂SO₄) = M × V = 0.245 mol/L × 20.0 mL / 1000 mL/L = 0.0049 mol

n(NaOH) = 2 × n( H₂SO₄) = 2 × 0.0049 mol = 0.0098 mol

V(NaOH) = n(NaOH) / M(NaOH) = 0.0098 mol / 0.610 mol/L = 0.016 m³ = 16 mL

Therefore, we need 16 mL of the 0.610 M NaOH solution to neutralize 20.0 mL of the 0.245 M  H₂SO₄ solution.

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Chemists use molarity to express concentration of solutions because it is convenient to determine molar concentration which helps us to find volume of the solution and weight of the solute.

Because it is simple and practical to apply, chemists express the concentration of solutions using molarity. It is possible to weigh the solute in grammes, convert its weight to moles, and combine it with a volume. The total molar concentration is equal to the molar concentrations added together.

Molarity is calculated as the number of moles of solute divided by the volume of the solution, and the volume of a solution depends on its density, which is a function of temperature.

Molarity = number of moles (n) / volume (L)

Due to its close association to moles, a term that connects the bulk measurement of substances to the microscopic and symbolic representations of chemistry, molarity is particularly beneficial to chemists.

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The galvanic cell is powered by the redox reaction between zinc and tin ions. At the cathode of the cell, reduction occurs and electrons are gained. In this case, the reduction half-reaction is Sn2+(aq) + 2e- → Sn(s).

At the anode of the cell, oxidation occurs and electrons are lost. In this case, the oxidation half-reaction is Zn(s) → Zn2+(aq) + 2e-.

E1 is the reduction potential of the tin half-reaction, which is -0.14 V. E2 is the oxidation potential of the zinc half-reaction, which is -0.76 V.

In solution S1, which is the electrolyte for the anode, there are zinc ions and sulfate ions. The chemical species in solution S2, which is the electrolyte for the cathode, are tin ions and sulfate ions.

Overall, the galvanic cell produces a flow of electrons from the anode to the cathode through the external circuit, while the ions in the electrolyte move from the anode to the cathode through the salt bridge. This creates a potential difference or voltage, that can be used to power an external device.

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Explanation:

you can count it by looking at the type of element

According to the pH scale, Option A) battery acid is the most strongest acid among all the substances mentioned.

The pH scale measures the acidity or basicity of a substance. It ranges from 0 to 14, with 7 being neutral. Values below 7 indicate acidity, with lower values indicating stronger acidity. Values above 7 indicate basicity, with higher values indicating stronger basicity. The scale is logarithmic, meaning that each whole number change represents a tenfold change in acidity or basicity. For example, a substance with a pH of 4 is ten times more acidic than one with a pH of 5.

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Complete question:

According to the pH scale, which of these substances is the strongest acid?

A) Battery acid

B) Lemon juice

C) Vinegar

D) Tomato juice

E) Black coffee

F) Milk

The empirical formula for magnesium oxide is MgO, indicating that there is one atom of magnesium and one atom of oxygen in the compound. We can find it in the following manner.

To find the empirical formula for magnesium oxide, we need to determine the mole ratio between magnesium and oxygen in the reactants and use that to write the simplest whole-number ratio of atoms in the compound.

First, we need to convert the masses of magnesium and oxygen to moles using their atomic masses:

Moles of magnesium = 48.62 g / 24.31 g/mol = 2.00 mol

Moles of oxygen = 32.00 g / 15.99 g/mol = 2.00 mol

Next, we need to determine the mole ratio by dividing each of the mole amounts by the smallest mole amount:

Moles of magnesium / smallest mole amount = 2.00 mol / 2.00 mol = 1

Moles of oxygen / smallest mole amount = 2.00 mol / 2.00 mol = 1

The mole ratio is 1:1, which means that the empirical formula of magnesium oxide is MgO.

Therefore, the empirical formula for magnesium oxide is MgO, indicating that there is one atom of magnesium and one atom of oxygen in the compound.

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Added sugars are various types of sugars and syrups that are added to food products during processing . Here are five common names for added sugars: Sucrose, Dextrose, Fructose, Maltose, High fructose corn syrup .

Sucrose: it is a disaccharide made up of glucose and fructose .

High fructose corn syrup: a sweetener made from cornstarch that has been processed to convert some of its glucose into fructose.

Dextrose: a simple sugar that is chemically identical to glucose and is commonly used in processed foods.

Fructose: a simple sugar found naturally in fruits, vegetables, and honey.

Maltose: a disaccharide made up of two glucose molecules and is commonly used as a sweetener in some beers and candies.

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The statement that the volume of space in the tube would be equal to the sum of the volumes of hydrogen and water vapor is true if the tube is exposed to the atmosphere.

The assertion might not be accurate, though, if the tube is inside a closed system.

It relies on the circumstances surrounding the tube's observation. Assuming the tube is at equilibrium and the hydrogen and water vapor are thoroughly mixed inside the tube, if the tube is open to the atmosphere, then the amount of space in the tube would indeed equal the combined volume of hydrogen and water vapor.

However, if the tube is in a closed system, like a sealed container, the volume of the space inside the tube might not be the same as the volume of the hydrogen and water vapor because the gas molecules there might be interacting with the container's walls or going through pressure or temperature changes. Consequently, the claim may be accurate or untrue depending on the specific context.

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Hexane has a higher boiling point than methanol due to differences in their intermolecular forces.

Hexane is a non-polar molecule with only weak London dispersion forces between molecules, whereas methanol is a polar molecule with strong hydrogen bonding and dipole-dipole forces between molecules.

Hydrogen bonding is a particularly strong intermolecular force because it involves the attraction between a hydrogen atom and an electronegative atom such as oxygen or nitrogen. In methanol, hydrogen bonding leads to strong intermolecular forces which require more energy to overcome, resulting in a higher boiling point. In contrast, hexane has only weak London dispersion forces, which are much less strong than hydrogen bonding, leading to a lower boiling point.

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Actually, methanol has a higher boiling point than hexane. Methanol has a boiling point of 64.7°C while hexane has a boiling point of 69°C.

The reason for this difference is due to the intermolecular forces between the molecules. Methanol is a polar molecule, which means it has a positive and negative end due to the difference in electronegativity between carbon and oxygen. This allows methanol molecules to form hydrogen bonds with each other, which are stronger intermolecular forces than the London dispersion forces present in nonpolar molecules like hexane. Therefore, methanol requires more energy to break the hydrogen bonds between its molecules, which results in a higher boiling point than hexane.

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A tumbler of water is mixed with a crystalline of green dye. There will be spread of the dye. Diffusion refers to the method of a substance spreading, which is shown by viewing the row of beakers spanning left to right.

According to its official definition, osmosis is the process by which water diffuses across a membrane in order to move from an area with a high hydraulic conductivity (low solute concentrations) to one with a low potential for water (high solute concentration).

When we put a drop of dye to a gelatin or gelatin plate at a certain location, it will eventually spread across the surface as the dye molecules are randomly migrating from their initial place in the gel. This is how we may detect diffusional movement using dyes.

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pH = 1.77  = acidic

* [OH^-] = 4.9 x 10^-5 =basic

* pOH = 5.14 = basic

* [H^+] = 1.0 x 10^-7  = neutral

* [H^+0 = 1.9 x 10^-5 =acidic

* pOH = 7.00  = neutral

* pH = 9.06 = basic

* [H^+] = 5.0 x 10^-10 = acidic

* pOH = 13.53 = acidic.

* [OH^-] = 4.6 x 10^-12 = basic

Specific heat of the metal is approximately 0.301 J/gºC (option a).

Let's discuss it further below.

The specific heat of the metal can be calculated using the formula:

q = mcΔT

where q is the heat absorbed (10000 J), m is the mass of the metal (400 g), c is the specific heat, and ΔT is the change in temperature (103.0 ºC - 20.0 ºC).

Step 1: Calculate ΔT:
ΔT = 103.0 ºC - 20.0 ºC = 83.0 ºC

Step 2: Rearrange the formula to solve for c:
c = q / (mΔT)

Step 3: Plug in the given values and solve for c:
c = 10000 J / (400 g * 83.0 ºC) = 10000 J / 33200 gºC ≈ 0.301 J/gºC

So, the specific heat of the metal is approximately 0.301 J/gºC (option a).

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To find the pH of a 0.38 M solution of a weak acid with a given acid dissociation constant (Ka), we can use the following formula:

Ka = [H+][A-]/[HA]

where [H+] is the concentration of hydrogen ions, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the weak acid.

First, we need to find the concentration of the conjugate base (A-) in the solution. This can be done using the following formula:

[A-] = [HA] * (Ka / [H+])

Plugging in the values given in the problem, we get:

[A-] = 0.38 * (8.4×10−6 / [H+])

Next, we can use the law of mass action to find the concentration of hydrogen ions in the solution:

Ka = [H+] * [A-] / [HA]

Plugging in the values we just found, we get:

8.4×10−6 = [H+]^2 / (0.38 * [H+])

Solving for [H+], we get:

[H+] = 1.0×10^-3 M

Finally, we can use the formula for pH to find the pH of the solution:

pH = -log([H+])

Plugging in the value we just found, we get:

pH = -log(1.0×10^-3) = 3.00

Therefore, the pH of a 0.38 M solution of a monoprotic weak acid with a Ka of 8.4×10−6 is approximately 3.00.

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The percent ionization of a 0.337 M HF solution can be calculated using the Ka of HF, which is 3.5 x 10-4.

The percentage oxidized indicates what proportion of the starting substance has been converted into ions.

As a result, we evaluate the concentration of the ion in solution by contrasting it to the initial concentration of the neutral species.

In a particular solution of a mild acid, the percentage of ionization will change depending on the initial concentration of the acid, and it will get lower as the concentration of the acid gets higher.

1. Write the ionization equilibrium expression for HF:
  HF ⇌ H+ + F-
  Ka = [H+][F-] / [HF]

2. Assume 'x' is the concentration of H+ and F- ions at equilibrium, so:
  Ka = (x)(x) / (0.337 - x)

3. Plug in the given Ka value (3.5 x 10^-4) and solve for 'x':
  3.5 x 10^-4 = (x)(x) / (0.337 - x)

4. Solving for 'x' using a calculator or a suitable approximation method, you will get the value of 'x', which represents the equilibrium concentration of H+ ions.

5. Calculate the percent ionization by dividing the concentration of H+ ions (x) by the initial concentration of HF (0.337 M) and multiplying by 100:
  % ionization = (x / 0.337) x 100

Using this method, you can find the percent ionization of the 0.337 M HF solution.

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Answer:

d < c < a < b

Explanation:

The molar mass of a compound is the sum of the atomic masses of all the atoms in its chemical formula. Here are the molar masses of the four compounds you have:

a. SiH4: (1 × 28.09 g/mol) + (4 × 1.01 g/mol) = 32.13 g/mol

b. Co: 58.93 g/mol

c. CH3OH: (1 × 12.01 g/mol) + (4 × 1.01 g/mol) + (1 × 16.00 g/mol) = 32.05 g/mol

d. C2H6: (2 × 12.01 g/mol) + (6 × 1.01 g/mol) = 30.07 g/mol

So, from smallest to largest molar mass, the order is: d < c < a < b.

The final temperature is 280.59 degrees Celsius.

The term atmospheres (atm), defined as follows: A mercury column one millimetre high would impose a pressure of one atm, or 1.01325 x 105 Pa. millimetres of mercury (mmHg). One atmosphere of pressure is generated by a mercury column that is 760 mm high. Because pressure and force are connected, you may use the physics equation to compute one if you know the other.

P1V1/T1 = P2V2/T2

Where P1, V1, and T1 are the initial pressure, volume, and temperature, and P2, V2, and T2 are the final pressure, volume, and temperature.

Given:

Initial pressure (P1) = 1.015 atm

Initial volume (V1) = 9.00 L

Initial temperature (T1) = -211.76 °C (62.39 K)

Mass of hydrogen gas initially (m1) = 2.035 g

Additional mass of hydrogen gas added (m2) = 2.099 g

Final pressure (P2) = 20.15 atm

PV = nRT

n1 = m1/MH2 = 2.035 g / 2.016 g/mol = 1.011 mol

n2 = m1/MH2 + m2/MH2 = 2.035 g / 2.016 g/mol + 2.099 g / 2.016 g/mol = 2.059 mol

We can assume that the volume of the container is constant, so we can set V1 = V2 in the combined gas law equation:

P1/T1 = P2/T2

Solving for T2:

T2 = P2T1V1 / (P1*V2)

Substituting the values:

V2 = V1 = 9.00 L

T2 = (20.15 atm)(62.39 K)(9.00 L) / (1.015 atm)(2.059 mol)(8.314 J/(mol*K))

T2 = 553.75 K or 280.59 °C

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Question:

A container holds 2.035 grams of hydrogen gas at a pressure of 1.015 atm and a temperature of -211.76 °C. What will be the temperature in °C if an additional 2.099 grams of hydrogen gas is added to the container and the pressure increases to 20.15 atm?

The organelle heavily involved in providing runner's cells with energy during the last leg of a 5K run is the mitochondria

The organelle heavily involved in providing the runner's cells with energy during the last leg of a 5K run is the mitochondria. Mitochondria are referred to as the "powerhouses" of the cell because they are responsible for producing the energy currency of cell, ATP (adenosine triphosphate), through the process of cellular respiration. During exercise, demand for ATP increases, and mitochondria works harder to meet this demand by breaking down glucose and other fuel molecules to generate ATP. Therefore, runner's cells would require a high level of mitochondrial activity to provide them with energy needed to complete the run.

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After a helium flash, which occurs in the core of a star during the later stages of its evolution, the star enters a stable phase of helium burning. During the flash, helium ignites explosively, producing a burst of energy that causes the core to expand and cool.

However, once the temperature and pressure in the core have reached the required levels again, helium burning resumes, producing energy and keeping the star stable. This process continues until the star exhausts its helium fuel, at which point it may undergo further nuclear reactions or collapse, depending on its mass. The helium flash is a crucial stage in the evolution of low- to medium-mass stars, allowing them to continue burning and shining for billions of years.

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When titrating if an indicator was not added, you would see: no color change and it would not be clear when the equivalence point was reached. The correct option is Option A.

Titrating is the process of analyzing or measuring the concentration of a solution (titrant) by adding a solution with a known concentration (titrant) drop by drop until the chemical reaction is complete. At the point when the chemical reaction is complete, we have reached the equivalence point.

An indicator is added to change color when the solution reaches the equivalence point, allowing us to precisely measure the endpoint. The indicator gives an observable signal, typically a color change, to show that the endpoint has been achieved. In the absence of an indicator, there would be no signal to indicate the endpoint was reached.

The equivalence point would still be identifiable, but it would be more difficult to precisely determine the endpoint. Titrations that rely on indicators are typically used to determine the concentration of an unknown acid or base solution. The type of indicator used varies based on the pH range of the unknown solution.

For example, methyl orange and phenolphthalein are indicators used in the titration of acids and bases, respectively.

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The entropy change for a particle in this gaseous system is negative and given by -k ln(2.404). This means that the system becomes less disordered as a result of the change in temperature and volume.

The entropy change for a particle in this gaseous system can be calculated using the Boltzmann entropy formula:

S = k ln(W)

where S is the entropy, k is the Boltzmann constant, and W is the number of microstates.

Since the final number of microstates is 0.418 times that of the initial number of microstates, we can write:

W_final = 0.418 * W_initial

Taking the natural logarithm of both sides, we get:

ln(W_final) = ln(0.418) + ln(W_initial)

Substituting this into the entropy formula, we have:

S_final - S_initial = k ln(W_final) - k ln(W_initial)

= k [ln(0.418) + ln(W_initial)] - k ln(W_initial)

= - k ln(2.404)

Therefore, the entropy change for a particle in this gaseous system is negative and given by -k ln(2.404). This means that the system becomes less disordered as a result of the change in temperature and volume.

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In a recrystallisation process, newly formed crystals are washed with cold solvent A. to wash off any impurities that have crystallized on the surface of the pure crystals.

Recrystallization is a process that is used to purify compounds in which they are recrystallized from a solvent. A sample that has impurities is dissolved in a minimum quantity of hot solvent to give a concentrated solution, which is then cooled slowly to enable the pure crystals to form, and then the crystals are washed with cold solvent. Recrystallization is carried out using a solvent in which the impurities have low solubility, the compound has high solubility, and the solvent does not react with the compound.

Recrystallization is essential since the compound's purity can affect the chemical properties of the substance. The process of washing the newly formed crystals is to remove any impurities that may have formed on the surface of the pure crystals. Cold solvent is used because it has low solubility, and it cannot dissolve the crystals, making it possible to wash off the impurities without dissolving the crystal.Aside from removing the impurities, washing the crystals with cold solvent also helps in getting rid of the solvent that contains impurities. The washing process is essential to achieve the maximum purity possible when recrystallizing a sample. Therefore the correct option is A

The complete question is :

In a recrystallisation, why are the newly formed crystals washed with cold solvent?

a.

To wash off any impurities that have crystallized on the surface of the pure crystals.

b.

To wash off the film of solvent which contains the impurities.

c.

To cool down the crystals.

d.

To slightly dissolve the crystals to give them a more rounded shape.

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Answer: 2.22 moles

Explanation:

Molar mass

The molar mass of water, or H2O, can be found by adding the molar mass of two hydrogen atoms and the molar mass of one oxygen atom, which comes out to be 18.0 g/mol.

To find the moles in 40.0 grams of water, we will set up a proportion.

[tex]\frac{18.0 g}{1 mol} =\frac{40.0g}{xmol} \\[/tex]

Then, we just solve for x.

[tex]18=\frac{40}{x} \\x=\frac{40}{18} \\x=2.22 mol[/tex]

40.0 g of water is 2.22 moles.