. which statement best describes how to choose the most suitable solvent to purify a solid by recrystallization

Answers

Answer 1

The compound to be purified must be soluble in the hot solvent and insoluble in the cold solvent. This is because during recrystallization, the compound is dissolved in the hot solvent to remove impurities, and then cooled to allow the compound to crystallize out of solution. If the compound is insoluble in the cold solvent, it will form pure crystals while impurities remain in solution. So the correct option is D.

Choosing the right solvent for recrystallization is crucial to ensure that the process is effective in purifying the compound. The solvent must be able to dissolve the compound at high temperatures to remove impurities, but then allow the compound to crystallize out of solution as the solvent cools.

By selecting a solvent in which the compound is soluble at high temperatures but insoluble at low temperatures, pure crystals of the compound can be obtained.

The complete question is given below

"

Which statement below best describes the reasoning behind choosing the most

suitable solvent to purify a sold by recrystalization ? Clearly choose one answer.

a) The compound to be purified must be soluble in both the hot solvent and the

cold solvent.

b) The compound to be purified must be insoluble in both the hot solvent and

the cold solvent.

c) The compound to be purified must be insoluble in the hot solvent and

soluble in the cold solvent.

d) The compound to be purified must be soluble in the hot solvent and

insoluble in the cold solvent.

"

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Related Questions

Which of the following contains the MOST atoms? You shouldn't need to do a calculation here.
O 10.0 g Mg
O 10.0 g Ne
O 10.0 g Kr
O 10.0 g Ar
O 10.0 g He

Answers

The substance with the most atoms is He (10.0 g), since it has the lowest molar mass (4.00 g/mol).

What is Atom?

An atom is the basic unit of matter that is composed of three types of subatomic particles: protons, neutrons, and electrons. Atoms are incredibly small and are the building blocks of all matter in the universe.

The nucleus of an atom is made up of positively charged protons and neutral neutrons. The number of protons in an atom's nucleus determines its atomic number, which defines its unique chemical identity. The electrons, which are negatively charged, orbit the nucleus in shells and interact with other atoms to form chemical bonds.

The number of atoms in a substance is determined by its molar mass, which is the mass of one mole of the substance in grams. One mole of any substance contains Avogadro's number of atoms, which is approximately 6.022 x 10^23.

The molar masses of the given substances are:

Mg: 24.31 g/mol

Ne: 20.18 g/mol

Kr: 83.80 g/mol

Ar: 39.95 g/mol

He: 4.00 g/mol

Since the amount of each substance is the same (10.0 g), we can compare the number of atoms by comparing their molar masses. The substance with the lowest molar mass will contain the most atoms, since the same mass of that substance corresponds to a greater number of moles.

Therefore, the substance with the most atoms is He (10.0 g), since it has the lowest molar mass (4.00 g/mol).

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Three aqueous solutions of different volumes are prepared. One is 3 m in glucose, one is 3 m in fructose, and one is 3 m in ethanol (C2H5 OH). Which of the following must these solutions have in common? Select all that apply: They all have the same density They contain the same total number of moles of solute They contain the same mass of solute. They have the same boiling points.

Answers

The three solutions with different volumes, all being 3M in glucose, fructose, and ethanol must contain the same total number of moles of solute.

This is because the concentration of each solution is the same, and the number of moles of a substance is directly proportional to its concentration and volume. Therefore, if the concentration is the same for each solution, the total number of moles of solute must also be the same. However, the solutions may not necessarily have the same density, mass of solute, or boiling points. The density of a solution is affected by factors such as temperature and pressure, and the mass of solute depends on the molar mass of each solute. The boiling point of a solution is influenced by the concentration and identity of the solutes, as well as external factors such as pressure.

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When a particular ionic solid begins to dissolve in water, the temperature rises dramatically. For the dissolution of this solid in pure water we can state that __O Lattice energy is larger than enthalpy of hydration in magnitudeO Enthalpy of solvation is positiveO Enthalpy of hydration is positiveO Enthalpy of solution is negativeO Enthalpy of solution is positive

Answers

The rise in temperature during the dissolution of an ionic solid in water is a result of the release of energy, indicating that the process is exothermic.

The enthalpy of solution is the difference between the energy required to separate the ionic solid into its constituent ions, known as the lattice energy, and the energy released during the hydration of these ions by water molecules. Since the dissolution of the solid is exothermic, the enthalpy of solution is negative. Therefore, we can state that the correct answer is "O Enthalpy of solution is negative" . Additionally, since the temperature rises dramatically during the dissolution of the ionic solid, it indicates that the magnitude of the lattice energy is greater than the enthalpy of hydration of the ions in water.

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what is the multiplicity of the indicated carbon in an off resonance decoupled c 13 nmr spectrum in off resonance decoupled spectra, direct 13 ch coupling is observed

Answers

There will be two results observed by 13C-NMR spectrum- First at 31 ppm signal is for the more shielded and electron-rich carbon atoms and is upfield. And second at 70 ppm  signal is directed downfield and pertains to the carbon atom, which is more exposed and has an environment poor in electrons.

What is 13C- NMR?

The use of nuclear magnetic resonance (NMR) spectroscopy on carbon is known as carbon-13 (C13) nuclear magnetic resonance, often known as carbon-13 NMR spectroscopy or 13C NMR spectroscopy, or simply as carbon NMR.

Similar to proton NMR (1 H NMR), it enables the identification of carbon atoms in an organic molecule in the same way that proton NMR identifies hydrogen atoms. The only isotope that 13C NMR can detect is 13 C. The predominant carbon isotope, 12 C, is not found.

Therefore 13C NMR spectroscopy is widely used for characterizing organic and organometallic compounds.

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For each of the following compounds, predict the energy barrier to rotation (looking down any one of the C—C bonds). Draw a Newman projection and then compare the staggered and eclipsed conformations. Remember that we assigned 4 kJ/mol to each pair of eclipsing H’s and 6 kJ/mol to an H eclipsing a methyl group:
(a) 2,2-Dimethylpropane
(b) 2-Methylpropane

Answers

(a) The steric hindrance brought on by the large methyl groups in 2,2-dimethylpropane results in a rather high energy barrier to rotation.

The lowest amount of energy necessary for a chemical reaction to take place is referred to as the energy barrier, also known as the activation energy. It is the amount of energy needed for the reactants to reach the transition state or the reaction's maximum energy location. The size of the energy barrier controls how quickly a reaction happens; a higher barrier causes a slower rate of reaction. Catalysts are frequently utilised to offer an alternate pathway that takes less energy to move forward in order to lower the energy barrier. Grasp chemical kinetics and creating chemical reactions with appropriate reaction rates require an understanding of the energy barrier concept.

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The ratio mol of soluteL of solution is called the _____ of a solution (symbol M), whereas the _____ (symbol m) of the solution is expressed as mol of solutekg of solvent. For an aqueous solution, these two quantities will be very similar if the solution concentration is _____.
molarity; molality; low

Answers

The molarity of a solution (symbol M) is the ratio of mol of solute to kg of solvent in the solution, whereas the molality (symbol m) is the ratio of mol of solute to kg of solvent in the solution.

What does molarity M mean?

The quantity of a material in a specific volume of solution is known as its molarity (M). The number of moles of a solute per liter of a solution is known as molarity. The molar concentration of a solution is another name for molarity.

What does molarity mean simply?

A solution's concentration can be determined by measuring its molarity. It is employed to figure out how much solute or solvent is present. The number of moles of a solute is used to calculate the molarity, or concentration, of a solution or other material in solution.

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4. If you were to place the skater at the 5-meter mark, how high would the skater go on the other side of the track? Write your prediction, then try it and state whether it matched your prediction or not and, if not, what happened instead.

Answers

If the skater starts at the 5-meter mark, I predict that the skater will reach the same height on the other side of the track. This is because the parabolic shape of the skater's trajectory is symmetrical, meaning that if the skater reaches a certain height at one point, they will reach the same height at the same distance on the opposite side.

This prediction can be tested by drawing a parabolic shape to represent the skater's trajectory and finding the height at the 5-meter mark and the 5-meter mark on the other side of the track.

The process of photosynthesis produces which of the following? HELP

oxygen

carbon dioxide

energy

glucose

Answers

Answer:

Explanation:

glucose and oxygen

What is the rate law for this reaction? Express the rate law symbolically in terms of k, [A], and [B].
Consider the reaction A + 2B → C whose rate at 25° C was measured using three different sets of initial concentrations as listed in the following table:
Trial [A] (M) [B] (M) Rate (M/s)
1 0.30 0.050 5.4 x 10^-3
2 0.30 0.100 1.1 x 10^-2
3 0.60 0.050 2.2 x 10^-2

Answers

The rate becomes:  0.0225 m/sec which symbolically in terms of k, [A], and [B]. Consider the reaction A + 2B → C whose rate at 25° C.

What is rate constants?

The rate constant is the quantity that expresses the connection between the molar concentration of the reactants and the rate of the chemical reaction. The rate constant rises as the reactant concentrations fall. Even if the reactant concentrations fluctuate, the rate constant remains constant. Depending on the kind of reaction and which reactants' concentrations vary, the rate constant will change. The proportionality constant (k) that links the pace of the reaction to reactant concentrations is known as the specific rate constant.

now calculate the rate constant using first equation

rate = k[A]²[B]

take the first row from table it not necessary you can take any

6.0×10⁻⁴ = K[0.1]²[0.05]

K = (6.0 × 10⁻⁴) / (5 × 10⁻⁴)

K = 1.2 mol⁻² lit² sec⁻¹

now use the same equation

substitute the given concentration and use the same K value find the rate constant

rate = k[A]²[B]

rate = 1.2 [0.5]²[0.075]

rate = 0.0225 m/sec

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What is the molecular formula for a compound that is 92.24% carbon and 7.76% hydrogen and has a molar mass of 78.12g?

Answers

The empirical formula of a compound gives the whole number ratio of atoms of various elements. The molecular formula of the compound is C₆H₆.

What is Molecular formula?

The molecular formula of a compound is defined as the formula which gives the actual number of atoms of various elements present in one molecule of the compound.

Here 92.24 % 'C' = 92.24 g

7.76 % 'H' = 7.76 g

Number of moles (n) = Given mass / Molar mass

'n' of 'C' = 92.24 / 12 = 7.68 moles

'n' of 'H' = 7.76 / 1 = 7.76 g

Number of atoms of 'C' = 7.68 / 7.68 = 1

Number of atoms of 'H' = 7.76 / 7.68 = 1

So empirical formula is CH.

The molecular weight of CH = 13

Number of atoms of each element = 78.12 / 13 = 6

Thus the molecular formula is C₆H₆.

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what is the name for the ion element Na+

Answers

sodium ion is Na+

hope this helps

There are two stable isotopes of chlorine: chlorine -35 and chlorine-37. Given that the average atomic mass of a chlorine atom is 35.45 amu, which if the following statements is true? A. chlorine contains almost exclusively Cl-37 with very little Cl-35 B. Chlorine contains more Cl-35 than Cl-37 C. Chlorine contains roughly equal amounts of Cl-35 and Cl-37 D. Chlorine contains more Cl-37 than Cl-35

Answers

Given that the average atomic mass of a chlorine atom is 35.45 amu, then the true statement would be that Chlorine contains roughly equal amounts of Cl-35 and Cl-37. The correct answer is C.

The average atomic mass of an element is the weighted average of the masses of its naturally occurring isotopes. In the case of chlorine, the atomic mass of the two stable isotopes (chlorine-35 and chlorine-37) is close to each other.

Chlorine-35 has an atomic mass of 34.97 amu and makes up about 75% of naturally occurring chlorine atoms, while chlorine-37 has an atomic mass of 36.97 amu and makes up about 25% of naturally occurring chlorine atoms.

The average atomic mass of chlorine can be calculated using the following formula:

average atomic mass = (fractional abundance of isotope 1 x mass of isotope 1) + (fractional abundance of isotope 2 x mass of isotope 2)

average atomic mass = (0.75 x 34.97 amu) + (0.25 x 36.97 amu)

average atomic mass = 26.23 amu + 9.24 amu

average atomic mass = 35.47 amu

This is very close to the reported average atomic mass of chlorine (35.45 amu), which confirms that chlorine contains roughly equal amounts of Cl-35 and Cl-37.

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Atoms of an element ex having two valence of electrons come into contact with element why that has seven valence electrons. Which of these statements is probably not true? A the compound is ionic. B two different ions are formed. C X +1 is formed D Y -1 is formed E none of these

Answers

The statement X +1 is formed is not true.

How is an ionic compound formed?

Ionic substances are formed through the process of ionization, which occurs when atoms or molecules gain or lose electrons. This results in the formation of ions, which are charged particles. When ions of opposite charge come together and form a crystal lattice structure, an ionic substance is formed.

For example, when a metal atom reacts with a non-metal atom, the metal atom can lose electrons to the non-metal atom, forming positively charged ions (called cations) and negatively charged ions (called anions). These ions are held together in a repeating pattern by ionic bonds, which are strong electrostatic forces. The resulting substance is an ionic compound.

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order the following steps of the chymotrypsin mechanism. not all steps may be given. top label: deprotonation of ser by hisdeprotonation of ser by his

Answers

I assume that the prompt got cut off. Based on the given information, the correct order of the steps of the chymotrypsin mechanism is:

Deprotonation of Serine (Ser) by Histidine (His).Attack of the peptide bond by the deprotonated Serine hydroxyl group.Formation of a tetrahedral intermediate.Collapse of the tetrahedral intermediate and cleavage of the peptide bond.Release of the first product and formation of an acyl-enzyme intermediate.

Note: The prompt seems to be asking for two labels, but only one label is given. Therefore, I provided the answer assuming that the label provided refers to the first step of the chymotrypsin mechanism.

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Which of the following salts would give you the highest concentration of phosphate ions in solution if you placed 1 mole of the salt in a liter of water?
Select one:
a. Ba³(PO⁴)²K³p =1.3 x 10–²⁹
b. Pb³(PO⁴)² K³p= 3.0 x 10–⁴⁴
c. Ca³(PO⁴)² K³p = 1.0 x 10–²⁵
d. Sr³ (PO⁴)² K³p = 1.0 x10—³¹

Answers

The salt that would give you the highest concentration of phosphate ions in solution if you placed 1 mole of the salt in a litre of water is the one with the highest Kₛp value. i.e. option B

The Kₛp value indicates the solubility product constant, which is a measure of the solubility of a salt in water.

The higher the Kₛp value, the more soluble the salt is in water, and therefore the higher the concentration of ions in solution.

Out of the given options, the salt with the highest Kₛp value is Pb³(PO⁴)² with a Kₛp value of 3.0 x 10–⁴⁴.

Therefore, this salt would give you the highest concentration of phosphate ions in solution if you placed 1 mole of the salt in a litre of water.

Therefore the correct option is (b.) Pb³(PO⁴)² K³p= 3.0 x 10–⁴⁴

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Explore the Model screen of the simulation. As you explore, answer the following questions. a.How does adding an atom affect the position of existing atoms or lone pairs? b. How does adding a lone pair affect the position of existing atoms and lone pairs?

Answers

The answers for multiple questions are given below.

(a)

When an atom is added it increases the effective nuclear charge which changes the position of existing atoms and lone pairs.

(b)

In the presence of additional lone pair, the lone pair - lone pair repulsions increases which affects the position of existing atoms and lone pairs.

Generally, lone pairs or often a single unpaired electron, electron pairs are defined as particles in bonds. Generally, the three additional pairs of electrons upon every atom are known as lone pairs, whereas the electron pair which are shared by the atoms is called as a bonding pair. Basically, the covalent bonding process excludes lone pairs.

The shape of the molecule is generally altered by the presence of an additional atom. Bonding electron pairs that lone electron pairs always resist one another since, electrons had same charge (i.e., negative charge).

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how do you balance a chemical reaction?

Answers

Balance a chemical reaction by placing the coefficients as needed in front of the symbols or formulas so the same number of each type of atom occurs in both reactants and products.

Each arrow shows an electron moving from one energy level to another. Which transitions will release energy?
A and D
only A
only C
B dan C

Answers

The Transition state  A and D will release energy.

When an electron moves from a higher energy level to a lower energy level, it releases energy. This can be seen in the diagram as the arrows pointing downwards. Therefore, transitions A and D will release energy, while transitions B and C will not.

It is important to remember that energy is always conserved, so when an electron moves from one energy level to another, the energy is not lost, but rather transferred in the form of light or heat.

In summary, the transitions that will release energy are A and D, as they involve an electron moving from a higher energy level to a lower energy level.

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Which of the following samples contain the greatest number of molecules?
1.00 grams of carbon monoxide
1.00 grams of carbon dioxide
1.00 grams of carbonate
All samples listed above have the same number of molecules

Answers

The sample contain the greatest number of molecules is 1.00 grams of carbon dioxide. Therefore, option B is correct.

What do you mean by the molecule ?

The term molecule is defined as the smallest component of a material that possesses both its chemical and physical characteristics. One or more atoms make up molecules.

There are three different kinds of molecules: atom-sized molecules, element-sized molecules, and compound-sized molecules.

1.00 grams of carbon monoxide,1.00 grams of carbon dioxide and 1.00 grams of carbonate, atoms present in these molecules are different so 1.00 grams of carbon dioxide  contain the greatest number of molecules.

Thus, option B is correct.

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according to this equation, how many moles of ammonia (nh3) were used if 12.2 moles of ammonium sulfate (nh4)2so4 were made?

Answers

If 12.2 moles of (NH₄)₂SO₄ were produced, then 6.1 moles of NH₃ were used.

Assuming the balanced chemical equation is:

2 NH₃ + H₂SO₄ → (NH₄)₂SO₄

This equation shows that two moles of ammonia are required for every one mole of ammonium sulfate produced. Therefore, to find the number of moles of ammonia used, we can use the following calculation:

moles of NH₃= moles of (NH₄)₂SO₄ / 2

moles of NH₃ = 12.2 moles / 2

moles of NH₃ = 6.1 moles

Therefore, if the balanced chemical equation is 2 NH₃ + H₂SO₄ → (NH₄)₂SO₄ and 12.2 moles of (NH₄)₂SO₄ were produced, then 6.1 moles of NH₃ were used.

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which compound can lower the freezing temperature of water, similarly to the antifreeze used in automobiles, and allow certain fish to remain active in very cold water? please choose the correct answer from the following choices, and then select the submit answer button. answer choices acetylcholine

Answers

"antifreeze proteins" or "ice-binding proteins", lower the freezing temperature of water, similarly to the antifreeze used in automobiles, and allow certain fish to remain active in very cold water.

Antifreeze proteins function by binding to ice crystals and preventing them from growing, which in turn prevents the formation of ice within the tissues of the organism. This allows the organism to remain active in very cold water, even when the water temperature is below the freezing point of pure water.

Acetylcholine is not a compound that can lower the freezing temperature of water.It is important to note that antifreeze proteins are a specialized adaptation that has evolved in certain organisms to help them survive in extremely cold environments, and they should not be confused with the antifreeze used in automobiles, which is a mixture of chemicals designed to lower the freezing point of the liquid in a car's cooling system.

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Which transformation will create $Q'R'S'T'$ , a quadrilateral that is similar but not congruent to quadrilateral $QRST$ ?

Answers

To create a quadrilateral that is similar but not congruent to another quadrilateral, you can apply a non-uniform dilation transformation.

What is non-uniform dilation transformation?

A non-uniform dilation transformation changes the size of a shape by a different scale factor in different directions. This means that the corresponding sides of the similar figures will have different lengths, and the corresponding angles will have the same measure.

To apply a non-uniform dilation transformation to quadrilateral $QRST$, you would need to specify different scale factors for each direction. For example, you could specify a scale factor of 2 in the x-direction and a scale factor of 3 in the y-direction. The resulting transformed quadrilateral, $Q'R'S'T'$, would have sides that are twice as long as the corresponding sides in the x-direction and three times as long as the corresponding sides in the y-direction. The angles of $Q'R'S'T'$ would be the same as the angles of $QRST$.

It is important to note that a non-uniform dilation transformation will not preserve the ratios of side lengths between similar figures, so $Q'R'S'T'$ will not be congruent to $QRST$.

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A compound, C6H14, produces a 1H NMR spectrum with four dustinct signals. The steps made by the integral trace measure 21, 42, 28 and 7 mm. Complete the table below to show the number of protons associated with each signal. Integral Protons21 mm, 42 mm, 28 mm, 7 mm

Answers

Integral: Protons:

21 mm 1 proton

42 mm 2 protons

28 mm 2 protons

7 mm 3 protons

To determine the number of protons associated with each signal, we need to look at the relative areas under each peak in the NMR spectrum, which are represented by the integral trace. The integral trace values of 21, 42, 28, and 7 mm represent the relative areas under each of the four distinct signals in the NMR spectrum.

The general rule is that the area under a peak in an NMR spectrum is proportional to the number of protons giving rise to that signal. Therefore, we can assign the number of protons associated with each signal by comparing the relative sizes of the integrals.

In this case, the largest integral corresponds to the signal with 2 protons (42 mm), so we can assign 2 protons to that signal. We can then assign the number of protons associated with the other signals by using the ratio of the integrals. For example, the integral of 21 mm is roughly half the size of the 42 mm integral, so we can assign 1 proton to the signal with an integral of 21 mm.

Using this method, we can assign the number of protons associated with each signal as shown in the table above.

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What is the energy of a photon with a frequency of 7.07 × 10¹⁴ s⁻¹?
(h = 6.626 × 10⁻³⁴ J • s)

Answers

The energy of a photon with a frequency of 7.07 × 10¹⁴ s⁻¹ is 4.68 × 10⁻¹⁹ J.

What is Frequency?

Frequency is a measure of the number of cycles of a repeating event per unit time. It is commonly used to describe the oscillation of waves, such as sound waves or electromagnetic waves. The unit of frequency is hertz (Hz), which represents one cycle per second.

The energy (E) of a photon can be calculated using the equation:

E = hf

Given:

Frequency (f) = 7.07 × 10¹⁴ s⁻¹

Planck's constant (h) = 6.626 × 10⁻³⁴ J • s

Using the equation, we get:

E = hf

E = 6.626 × 10⁻³⁴ J • s × 7.07 × 10¹⁴ s⁻¹

E = 4.68 × 10⁻¹⁹ J

Therefore, the energy of a photon with a frequency of 7.07 × 10¹⁴ s⁻¹ is 4.68 × 10⁻¹⁹ J.

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the activation energy, ea, for a particular reaction is 37.8 kj/mol. if the rate constant at 280 k is 0.178 m/s, then what is the value of the rate constant at 445 k? (r

Answers

The rate constant at 445 K is 0.0122 m/s.

The rate constant at 445 K for the reaction with an activation energy of 37.8 kJ/mol can be calculated using the Arrhenius equation:

k = A*e^{(-Ea/RT)}

Where k is the rate constant at 445 K, A is the pre-exponential factor, Ea is the activation energy, R is the ideal gas constant (8.314 J/molK) and T is the temperature in Kelvin. Substituting the values given we get:


k = 0.178 * e^{(-37.8*10^3/(8.314*445)}


Therefore, the rate constant at 445 K is 0.0122 m/s.

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calculate the ph of 500 ml of water to which 15 ml of 1.0 m koh has been added. give your answer to 1 decimal point.

Answers

The pH of 500 ml of water to which 15 ml of 1.0 M KOH has been added is 12.4.

The volume of the water = 500 mL

The volume of the KOH = 15 mL

The total volume = 500 + 15

                            = 515 mL

                           = 0.515 L

The moles of the KOH = molarity × volume in L

The moles of the KOH = 1 × 0.015

                                      = 0.015 mol

The molarity = 0.015 / 0.515

Molarity = 0.029 M

The KOH dissociates is completely, the added [OH] is equal to the [KOH]

pOH = - log ( 0.029 + 10⁻⁷ )

The Hydroxide ion concentration in the water is  1.0 x 10-7M,  is ignored because it is much smaller .

pOH = - log (0.029)

pOH = 1.52

pH = 14 - pOH

pH = 14 - 1.52

pH = 12.4

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Which of the following statements regarding a correlation coefficient of 0.60 for two variables Y and X is most accurate? This correlation:
A) is significantly different from zero.
B) indicates a positive causal relation between the two variables.
C) indicates a positive covariance between the two variables.

Answers

The most accurate statement regarding a correlation coefficient of 0.60 for two variables Y and X is significantly different from zero. Option A is the correct answer.

A correlation coefficienb of 0.60 indicates a moderate positive relationship between the two variables, which is significantly different from zero. This means that there is a statistically significant association between the two variables, but it does not necessarily indicate a causal relationship or the direction of the relationship between the two variables.

Additionally, the correlation coefficient measures the strength and direction of a linear relationship between two variables, and does not capture non-linear relationships or other types of associations between the variables.

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A designated driver is one who, in a group of two or more people that will be drinking, agrees to drink only one or two alcoholic beverages and then drive the others home safely.
True or False?

Answers

The given statement is false.

What is alcoholic beverages ?

Any fermented beverage that contains the intoxicating ingredient ethanol (CH3CH2OH), such as wine, beer, or distilled spirits, is considered to be an alcoholic beverage. The discussion on alcoholic beverages is brief.

What is drive ?

Driving refers to controlling or riding in a motor vehicle. Drive a go-kart, a bus, or a car. Drive is one of those multipurpose words with several applications. In a broad sense, it has to do with pushing or pushing in a certain direction; drive and go go hand in hand.

Therefore, given statement is false.

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Based on the data table, one scientist concludes that the mass of PbCr04
formed depends only on the amount of K₂CrO4 added, and another scientist
concludes that the mass of PbCrO4 formed depends on the amount of the
limiting reactant. How might this conflict be resolved?
Sample IM HCI
(mL)
50
50
25
1
2
3
2M AgNO3
(ml)
50
25
50
AgCl
formed (g)
7.2
7.2
3.6
OA. Experiment further, using different amounts of each reactant as
the limiting reactant.
B. Write the balanced chemical equation for this reaction and
compare proportions resulting from the equation.
OC. Assume the same reactant is limiting in each trial.
O D. Determine how each scientist's background affects the
conclusions.
as anderes

Answers

The yield of a reaction depends on the limiting reactant of the reaction. Hence, write the balanced chemical equation for this reaction and compare proportions resulting from the equation.

What is limiting reactant ?

A limiting reactant in a reaction is the reactant which is fewer in amount or consume early without complete reaction with other reactants. Hence, as soon as this reactant is consume, the reaction stops.

For the given reaction, we must write the balanced reaction for the formation of the product lead chromate.  By writing the equation, we can understand the correct stoichiometry of each reactants and products.

The reactant which is taken in lower quantity than what is required for complete reaction with the reagents will determine the  reaction yield and the amount of product formed.

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you would expect human red cells to shrink in which of the following solutions: 0.2m nacl 0.2m surcrose 0.2m urea

Answers

You would expect human red cells to shrink in  0.2 M NaCl. The correct answer is A.

Red blood cells have an ion concentration of roughly 300mM, or 300 milliosmolality. Essentially, it indicates that the concentration of all the dissolved ions in a red blood cell is roughly 300 mM, or 0.3M.

Where there is a higher concentration of water, it moves toward a lower concentration. Water flows from lower osmolarity to higher osmolarity, or put another way (since water is higher in concentration in a lower osmolarity solution).

Since a solution of 0.2M NaCl has an osmolarity of 0.4M, the water concentration in red blood cells is higher. This implies that the red blood cell will shrink and shrivel when water flows OUT of it.

Urea 0.2M is a dissolved solute even though it is not ionic. Water will somewhat enter the red blood cell since it is less concentrated than the red blood cell. (assumes red blood cells with 0.3M osmolarity).

In a hypotonic condition, a red blood cell will enlarge and go through hemolysis (burst). A red blood cell will crenate and lose water when it is placed in a hypertonic solution (shrivel). Animal cells typically function best in an isotonic environment, in which the rate of water flow into and out of the cell is equal.

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