what caused the newt population to become more poisonous

In summary, a bond having "more ionic" or "more covalent" character refers to the degree to which the bond is either purely ionic or purely covalent, with most bonds falling somewhere in between.

When a bond has more ionic character, it means that the electrons are transferred more completely from one atom to another, resulting in larger differences in electronegativity and a greater degree of charge separation between the atoms. This typically occurs when there is a large difference in electronegativity between the atoms involved in the bond.

On the other hand, when a bond has more covalent character, it means that the electrons are shared more equally between the atoms, resulting in a smaller difference in electronegativity and less charge separation. This typically occurs when the atoms involved in the bond have similar electronegativities.

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The temperature of the sample of CO² gas is 87.41 Kelvin.

Combined gas law put together both Boyle's Law, Charles's Law, and Gay-Lussac's Law. It states that "the ratio of the product of volume and pressure and the absolute temperature of a gas is equal to a constant.

It is expressed as;

P₁V₁/T₁ = P₂V₂/T₂

At STP (standard temperature and pressure), the temperature is 273.15 K and the pressure is 1 atm.

Therefore, we can use the combined gas law to solve for the final temperature:

P₁V₁/T₁ = P₂V₂/T₂

Where P₁ = 1 atm, V₁ = 0.50 L, T₁ = 273.15 K, P₂ = 1.6 atm, V₂ = 0.10 L, and we are solving for T₂.

Substituting the values and solving for T2, we get:

T₂ = (P₂V₂T₁) / (P₁V₁)

T₂ = ( 1.6 atm × 0.10 L × 273.15 K) / (1 atm × 0.50 L)

T₂ = 87.41 K

Therefore, the temperature of the sample is 87.41 K.

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The electron configuration of Helium (He) is 1s², which means that it has two electrons in its outermost shell.

Helium is an inert gas and, like hydrogen, it also emits a line spectrum when it is energized.Helium has a more complex spectrum than hydrogen because it has more electrons.

As a result, it emits more lines than hydrogen. Helium has two electrons, which implies that it will have twice the number of lines than hydrogen.

The emission spectrum of helium will have more lines than that of hydrogen because helium has more electrons.

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In a cyclic voltammogram of an irreversible electrochemical reaction, only one peak is present (either anodic or cathodic) due to the limited reversibility of the reaction.

An irreversible reaction cannot be completely reversed so when the potential of the reaction is increased, the reaction will proceed in the same direction, leading to the formation of a single peak.

The peak represents the forward reaction, either the oxidation or reduction of the species in the reaction.

The magnitude of the peak depends on the rate of the forward reaction and the degree of reversibility of the reaction.

When the potential of the reaction is increased, the reaction will move further in the same direction, and the peak will become more prominent.

The peak will reach a maximum size when the reaction reaches its equilibrium potential, which occurs when the rate of the forward and reverse reactions are equal.

The magnitude of the peak also depends on the rate of diffusion of the species in the reaction. The peak will be smaller when the rate of diffusion is slow, and it will be larger when the rate of diffusion is fast.

The shape of the peak will depend on the degree of reversibility of the reaction, with more symmetrical peaks for reversible reactions and more asymmetrical peaks for irreversible reactions.

Only one peak is present in a cyclic voltammogram of an irreversible electrochemical reaction due to the limited reversibility of the reaction.

The magnitude of the peak is determined by the rate of the forward reaction, the rate of diffusion of the species, and the degree of reversibility of the reaction.

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Combustion has a constant enthalpy, Hc. The heat produced when 1 mol of a material burns fully in oxygen under typical conditions.

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To calculate the heat transferred by the chemical reaction, we can use the equation:

q = mcΔT

where q is the heat transferred, m is the mass of the solution, c is the specific heat capacity of the solution, and ΔT is the change in temperature.

Given:

m = 155 g

c = 4.184 J/g⋅K

ΔT = 26.5 ºC - 22.0 ºC = 4.5 ºC

Substituting these values into the equation, we get:

q = (155 g) x (4.184 J/g⋅K) x (4.5 ºC)

q = 29168.98 J or approximately 29.2 kJ

Therefore, the heat transferred by the chemical reaction to the calorimeter reservoir is 29.2 kJ.

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Answer:

The major ion in seawater is chloride.

Explanation:

Seawater is composed of various ions such as sodium, magnesium, sulfate, and chloride. However, the most abundant ion in seawater is chloride (Cl-), which accounts for approximately 55% of the total ion concentration. This is due to the fact that chloride is a relatively stable ion and does not react with other ions in seawater. Therefore, it tends to accumulate in seawater over time, making it the most prevalent ion in seawater.

Answer: THE ANSWER IS OPTION D) chloride.

Explanation: I GOT A 100 ON THE QUIZ ( please mark brainliest )

NaCl crystallizes in a cubic unit cell, meaning each side of the cell is equal in length. In this structure, each corner of the cell has a Cl- ion and each face of the cell has a Na+ ion, totaling 8 Cl- ions and 6 Na+ ions per unit cell. So, there are 8 Cl- ions and 6 Na+ ions in each unit cell of NaCl.

NaCl is an ionic compound, meaning it is composed of a metal cation (Na+) and a nonmetal anion (Cl-). Ionic compounds form when electrons are transferred from the metal to the nonmetal, creating a strong electrostatic attraction between the two ions. The oppositely charged ions are then arranged into a lattice structure with a repeating pattern of alternating cations and anions.

The unit cell of a NaCl crystal is a cube, meaning all the sides of the unit cell are of equal length. A single unit cell of NaCl contains eight Cl- ions at the corners and six Na+ ions at the faces of the cube. Since the unit cell of NaCl is symmetrical, the same arrangement of ions is repeated in each adjacent unit cell of the crystal. The arrangement of ions in a NaCl unit cell is important in understanding its properties. Because the cations and anions are arranged in an alternating pattern, the ions form a strong ionic bond. This bond gives the crystal its hardness and stability, making NaCl one of the most common and widely used compounds.

In summary, each unit cell of NaCl contains 8 Cl- ions at the corners and 6 Na+ ions at the faces, forming a cube of equal sides. The alternating arrangement of cations and anions creates an ionic bond which gives NaCl its hardness and stability.

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The remaining radioactivity after one day will be 0.0063% of the original radioactivity. This is because the half-life of a radioactive material is the amount of time it takes for half of the original radioactivity to decay. So, after one day, the original radioactivity will have decayed to 0.0063%.

The process through which an unstable atomic nucleus loses energy through radiation is known as radioactive decay, also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration. A substance that has unstable nuclei is regarded as radioactive. Alpha decay, beta decay, and gamma decay are three of the most frequent kinds of decay, and they all entail the emission of one or more particles. Beta decay is a result of the weak force, while the nuclear force and electromagnetism are in charge of the other two mechanisms.  Electron capture, which occurs when an unstable nucleus seizes an inner electron from one of the electron shells, is the fourth prevalent kind of decay. A series of electrons drop as a result of that electron being lost from the shell.

At the level of individual atoms, radioactive decay is a stochastic (i.e. random) process. No matter how long an atom has existed, quantum theory says it is impossible to forecast when an atom will decay. Nonetheless, the overall decay rate can be stated as a half-life or as a decay constant for a sizable number of similar atoms. There is a wide variation in the half-lives of radioactive atoms, from almost instantaneous to much longer than the age of the universe.

The remaining radioactivity after one day will be 0.0063% of the original radioactivity. This is because the half-life of a radioactive material is the amount of time it takes for half of the original radioactivity to decay.

1/2^(24/20) = 0.0063%.

Therefore, after one day, the original radioactivity will have decayed to 0.0063%.

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Answer:

I needed points

Explanation:

i need them

The pH of a buffer solution that is formed by mixing 85 ml of 0.13 M lactic acid with 95 ml of 0.14 M sodium lactate is 4.91.

A buffer solution is an aqueous solution that can resist changes in pH even when small quantities of acidic or basic substances are added to it. Buffers have the ability to maintain their pH in the presence of an acid or base. This is due to the presence of conjugate acid-base pairs in the buffer solution.

Calculation:Given:Initial concentration of lactic acid = 0.13 MInitial concentration of sodium lactate = 0.14 MVolume of lactic acid = 85 mlVolume of sodium lactate = 95 mlpKa of lactic acid = 3.86The Henderson-Hasselbalch equation for pH is:pH = pKa + log [A-]/[HA]where pKa is the acid dissociation constant, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the acid.In this problem, lactic acid (HA) is the acid and sodium lactate (A-) is the conjugate base.

We must first calculate the concentrations of the acid and its conjugate base.[HA] = 0.13 M x 85/180 ml = 0.0611 M[A-] = 0.14 M x 95/180 ml = 0.0737 M, Substitute the values of [A-], [HA] and pKa in the above equation, we get:pH = 3.86 + log (0.0737/0.0611)pH = 4.91Hence, the pH of the buffer solution is 4.91.

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The compound in which the oxidation state of oxygen is -1 is H2SO4, also known as sulfuric acid.

It is an inorganic, strong acid that has two hydrogen atoms, one sulfur atom, and four oxygen atoms. The oxidation state of oxygen in this compound is -1 because it has been oxidized by the sulfur atom, which has an oxidation state of +6.

The other compounds listed (KCH3COO, O2, H2O2, and H2O) do not have an oxidation state of -1 for oxygen. KCH3COO is potassium acetate, which has two oxygen atoms with oxidation states of -2 and +4, respectively. O2 is oxygen gas, which has an oxidation state of 0. H2O2 is hydrogen peroxide, which has two oxygen atoms with oxidation states of -1 and -1, respectively. Lastly, H2O is water, which has two hydrogen atoms and one oxygen atom, with the oxygen atom having an oxidation state of -2.

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Answer:

3.5 x 10^3 ml

Explanation:

We can use the ideal gas law to solve this problem:

PV = nRT

where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature in Kelvin.

First, we need to convert the volume to liters and the pressure to atmospheres:

V = 3.50 x 10^-3 L

P = 3185 mmHg / 760 mmHg/atm = 4.19 atm

Next, we can solve for T:

T = PV / nR

T = (4.19 atm) (0.505 mol) (0.08206 L atm mol^-1 K^-1) / (3.50 x 10^-3 L)

T = 1074 K

Therefore, at a temperature of 1074 K (801°C or 1474°F), 0.505 mole of CO2 will occupy a volume of 3.50 x 10^3 ml at a pressure of 3185 mmHg.

The empirical formula of the compound that produces 330 g of carbon, 69.5 g of hydrogen, and 440.4 g of oxygen upon decomposition is CHO2.

The empirical formula of a compound is the simplest whole-number ratio of atoms present in it. Follow the below steps to calculate the empirical formula of the given compound: Calculate the mass of each element present in the compound.

Calculate the mole of each element present in the compound by dividing its mass by its atomic mass. Determine the mole ratio by dividing each mole value by the smallest mole value obtained. Rearrange the ratio obtained in step 3 in the form of whole numbers. Moles of hydrogen/moles of oxygen = 69.5/27.5 = 2.53 ≈ 2.5Moles of oxygen/moles of oxygen = 27.5/27.5 = 1Therefore, the mole ratio of carbon: hydrogen: oxygen = 1: 2.5: 1Rearranging the above ratio to whole numbers, we get the mole ratio of carbon: hydrogen: oxygen as 2: 5: 2. The empirical formula of the compound is therefore CHO2.

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Answer:

8.35 atm.

Explanation:

The given reaction is:

2 CH4 → C2H4 + 2 H2

From the balanced equation, we can see that for every mole of C2H4 produced, 2 moles of H2 are produced.

First, we need to find the number of moles of C2H4 produced:

Molar mass of C2H4 = 2(12.01 g/mol) + 4(1.01 g/mol) = 28.05 g/mol

Number of moles of C2H4 = 11.6 g / 28.05 g/mol = 0.413 mol

Since 2 moles of H2 are produced for every mole of C2H4, the number of moles of H2 produced is:

0.413 mol C2H4 × 2 mol H2 / 1 mol C2H4 = 0.826 mol H2

Now we can use the ideal gas law to find the pressure of H2:

PV = nRT

where P is pressure, V is volume, n is the number of moles, R is the gas constant (0.0821 L·atm/K·mol), and T is temperature in Kelvin.

We are given the volume (2.4 L) and temperature (300 K), and we just calculated the number of moles (0.826 mol). Plugging these values into the ideal gas law:

P × 2.4 L = 0.826 mol × 0.0821 L·atm/K·mol × 300 K

P = (0.826 mol × 0.0821 L·atm/K·mol × 300 K) / 2.4 L

P = 8.35 atm

Therefore, the pressure of hydrogen gas is 8.35 atm.

The orientation of the glycosidic bond affects the properties of the polysaccharides it creates by determining the geometry of the sugar units in the polymer chain. When the glycosidic bond is in the alpha configuration, the sugar ring has a twisted conformation, which results in the sugar units being oriented in a more linear fashion.

In contrast, when the glycosidic bond is in the beta configuration, the sugar ring has a more planar conformation, which results in the sugar units being oriented in a more zig-zag fashion.

This difference in orientation affects the overall structure of the polysaccharide. Polysaccharides with alpha glycosidic bonds tend to form helical structures, while polysaccharides with beta glycosidic bonds tend to form sheet-like structures. This is because the twisted conformation of the alpha sugar units allows for the formation of hydrogen bonds between adjacent sugar units, which leads to the formation of a helix.

In contrast, the more planar conformation of the beta sugar units does not allow for the formation of hydrogen bonds between adjacent sugar units, which leads to the formation of a sheet.

Additionally, the orientation of the glycosidic bond affects the solubility and digestibility of the polysaccharide. Polysaccharides with alpha glycosidic bonds tend to be more soluble and more easily digested than polysaccharides with beta glycosidic bonds.

This is because the helical structure of alpha-polysaccharides allows for more surface area to be exposed to water and digestive enzymes, while the sheet-like structure of beta-polysaccharides does not.

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Answer:

0.972

Explanation:

The balanced chemical equation for the reaction is:

3 NaOH + H3PO4 → Na3PO4 + 3 H2O

From the equation, we can see that for every 1 mole of H3PO4 reacted, 3 moles of water are produced. Therefore, we need to first calculate how many moles of H3PO4 are present in 4.30 g of NaOH:

molar mass of NaOH = 23.0 g/mol + 16.0 g/mol + 1.0 g/mol = 40.0 g/mol

moles of NaOH = 4.30 g / 40.0 g/mol = 0.108 mol

According to the balanced equation, 3 moles of water are produced for every 1 mole of H3PO4. Therefore, we can calculate how many moles of water are formed as follows:

moles of H3PO4 = 3/1 * 0.108 mol = 0.324 mol

moles of water = 3/1 * 0.324 mol = 0.972 mol

Therefore, 0.972 moles of water are formed when reacting 4.30 g of sodium hydroxide with phosphoric acid.

Lindane (hexachlorocyclohexane) is an agricultural insecticide that can also be used to treat head lice. The lowest energy chair conformation of lindane is a slightly puckered chair conformation, which is a six-membered ring of alternating single and double bonds.  The hydrogen atoms are positioned in an axial orientation and the chlorine atoms are in an axial orientation.
Lindane (hexachlorocyclohexane) is an agricultural insecticide that can also be used in the treatment of head lice. The lowest energy chair conformation of lindane isThe lowest energy chair conformation of lindane is the one with the Cl atom and the H atom in equatorial positions. The molecule of lindane consists of six carbon atoms joined together in the form of a ring.Each carbon atom is attached to one hydrogen atom and one chlorine atom. The relative orientations of the C-H and C-Cl bonds determine the conformation of the molecule. The ring can assume various conformations, and the lowest energy conformation is the most stable. The conformation of the molecule can be analyzed by assigning axial and equatorial positions to the atoms on the carbon ring. In the axial position, the atoms are oriented perpendicular to the ring. In the equatorial position, the atoms are oriented at an angle of 120° with respect to the ring. The axial orientation is less stable than the equatorial orientation because the axial atoms experience steric hindrance from the other atoms on the ring. The steric hindrance is reduced in the equatorial orientation, and this results in a lower energy conformation. Thus, the lowest energy chair conformation of lindane is the one with the Cl atom and the H atom in equatorial positions.

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The correct formula for copper(II) phosphate is Cu3(PO4).

Copper (II) phosphate is a compound made up of copper ions and phosphate ions. Its chemical formula is Cu3(PO4)2. Copper(II) phosphate is a deep blue colour and has a high boiling point because of the strong bonds between the copper and phosphate ions.The chemical formula for copper(II) phosphate is Cu3(PO4)2.

A chemical formula is a collection of chemical symbols used to express the elements, atoms, and molecules in a chemical compound. They are a shorthand method of representing chemical compounds, and the chemical composition of molecules, elements, and atoms can be deduced from them. Chemical formulas are essential in chemistry because they provide the necessary details for reactions, such as how many atoms are present in a molecule or the number of each type of atom that is required to balance the equation.

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the radioactive decay of c14 which is used in estimating the age of archaeological  after 2500 years, 0.0027 mol of c14 remain in the sample.

The amount of c14 remaining after 2500 years can be calculated using the first-order rate equation:

N(t) = N0 * e^(-kt)

where N0 is the initial amount of c14, N(t) is the amount remaining after time t, k is the decay constant, and e is the base of the natural logarithm. The half-life of c14 is given as 5725 years, which means that k can be calculated as:

k = ln(2)/t1/2 = ln(2)/5725

Substituting the values given in the problem, we get:

k = ln(2)/5725 = 1.21 * 10^-4 /year

Now, we can use the rate equation to find the amount of c14 remaining after 2500 years:

N(2500) = 0.0035 * e^(-1.21*10^-4 * 2500) = 0.0027 mol

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The most likely identity of the unknown gas that effuses taking 37s is Oxygen(O₂).

Since the unknown gas effuses out faster, it must be lighter than Xe.

The most likely identity of the unknown gas can be determined using Graham's Law of Diffusion. According to this, the time taken for effusion/diffusion of two different gases under identical conditions is directly proportional to the square roots of their densities or molecular masses. It is given as:

t₂/t₁ = √(M₂/M₁)

where t₂,t₁ are the times taken and M₂, M₁ are the molecular masses.

This ratio is determined by the ratio of the molecular weights of the unknown gas and the sample of Xe. The heavier the molecular weight, the slower the rate of effusion.

Rearranging and plugging in the values as t₂= 75s, t₁= 37s,  M₁= 131g (for Xe), we get M₂ as follows:

M₂= (37/75)² x 131 = 31.8 ≈ 32g

32g corresponds to the molecular weight of O₂ and it is lighter than Xe.

Therefore, the unknown gas that effuses out of the container faster than the sample of Xe, resulting in the unknown gas taking 37 seconds, and the sample of Xe taking 75 seconds is oxygen(O₂).

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The volume of 0.150 M HNO3 that can be prepared from 0.350 L of 1.98 M HNO3 is 0.07112 L, or approximately 71.12 mL (since 1 L = 1000 mL).

The given equation is used to calculate the volume (V1) of a desired concentration of a solution (0.150 M HNO3) that can be prepared from a given volume (V2) of a known concentration solution (1.98 M HNO3), using the ratios of their concentrations (C1 and C2).

Let's break down the calculation step by step using the given values:

V2 (given volume) = 0.350 L

C1 (desired concentration) = 0.150 M

C2 (known concentration) = 1.98 M

Plugging these values into the equation, we get:

V1 (0.150 M HNO3) = V2 (1.98 M HNO3) x (C1 (0.150 M) / C2 (1.98 M))

V1 = 0.350 L x (0.150 M / 1.98 M)

V1 = 0.350 L x 0.0758

V1 = 0.07112 L

Therefore, the volume of 0.150 M HNO3 that can be prepared from 0.350 L of 1.98 M HNO3 is 0.07112 L, or approximately 71.12 mL (since 1 L = 1000 mL).

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If 0.0200 m fe3 is initially mixed with 1.00 m oxalate ion, then concentration of Fe3+ ion at equilibrium is 0 M.

The balanced chemical equation for the reaction of Fe3+ ion and oxalate ion is:

Fe3+ + 3C2O42- -> Fe(C2O4)33-

The reaction quotient, Qc, for the above reaction is given by the expression:

Qc = [Fe(C2O4)33-]/[Fe3+][C2O42-]

Here, the initial concentration of Fe3+ ion

= 0.0200 m

And, the initial concentration of oxalate ion is 1.00 m . According to the stoichiometry of the balanced equation, 1 mole of Fe3+ ion reacts with 3 moles of C2O42- ions to form 1 mole of Fe(C2O4)33- complex ion. Hence, the concentration of C2O42- ion that reacts with the given initial concentration of Fe3+ ion is given by the expression: [C2O42-] = 3[Fe3+] = 3 x 0.0200 m = 0.0600 m. After the reaction comes to equilibrium, let the concentration of Fe3+ ion be x M.Now, [Fe(C2O4)33-] = 0 M (as the entire Fe3+ ion is converted into Fe(C2O4)33- complex ion)Substituting the given and calculated values in the expression for Qc, we get:

Kc = [Fe(C2O4)33-]/[Fe3+][C2O42-]

=> 0/[x][0.0600]

=> 0x

=> 0 M

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Answer: If a plant produces 4.91 mol C6H12O6, then 6 x 4.91 = 29.46 moles of O2 are needed to produce 4.91 mol C6H12O6.

However, there is no given reaction, so it is not clear how O2 is involved. The balanced reaction equation for cellular respiration is:

C6H12O6 + 6O2 → 6CO2 + 6H2O + energy (ATP)

The ratio of CO2 to C6H12O6 is 6:1, which means 6 moles of CO2 is produced from every mole of C6H12O6 in the reaction. The ratio of O2 to C6H12O6 is 6:1 as well.


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Einstein's famous equation say that all matter is option B. concentrated energy that has condensed into the atoms.

When combined with the speed of light, Einstein's famous equation E=mc2 demonstrates mathematically that energy and matter are one and the same. m stands for mass, c for the speed of light, and E stands for energy. This equation states that all matter is simply concentrated energy that has condensed into atoms.

Einstein's famous equation is E=mc², which expresses the relationship between mass (m) and energy (E), and the constant speed of light (c) in a vacuum. This equation shows that mass and energy are interchangeable, and that a small amount of mass can be converted into a large amount of energy, as demonstrated in nuclear reactions.

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If the value of ΔG° is equal to 0, then the value of K or Kp is equal to 1 and the system is said to be in equilibrium.

A change in temperature occurs when heat flow increases or decreases the temperature. This changes the chemical equilibrium towards the products or the reactants. This can be identified by examining the reaction and determining whether it is an endothermic reaction or an exothermic reaction.

If the temperature is raised, the equilibrium constant decreases. If the forward reaction has an endothermic nature, the equilibrium constant increases. The equilibrium position also changes when the temperature is changed.

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When a 25.7 mL sample of a 0.494 M aqueous hydrofluoric acid solution is titrated with a 0.424 M aqueous sodium hydroxide solution, the pH after 44.9 mL of sodium hydroxide have been added is 8.71.

When a 25.7 mL sample of a 0.494 M aqueous hydrofluoric acid solution is titrated with a 0.424 M aqueous sodium hydroxide solution, the pH after 44.9 mL of sodium hydroxide have been added can be calculated using the Henderson-Hasselbalch equation. This equation states that the pH of a solution is equal to the pKa (the acid dissociation constant) plus the logarithm of the base-to-acid ratio. The pKa of hydrofluoric acid is 3.2 and the base-to-acid ratio is the molarity of the sodium hydroxide (0.424 M) divided by the molarity of the hydrofluoric acid (0.494 M). This gives a ratio of 0.855 and a pH of 7.12.

To calculate the pH of the solution after 44.9 mL of sodium hydroxide have been added, the volume of hydrofluoric acid solution added must be taken into account. Since 25.7 mL of the hydrofluoric acid solution was initially present, an additional 19.2 mL of sodium hydroxide must be added. Using the Henderson-Hasselbalch equation, this gives a base-to-acid ratio of 1.608 and a pH of 8.71.

In summary, when a 25.7 mL sample of a 0.494 M aqueous hydrofluoric acid solution is titrated with a 0.424 M aqueous sodium hydroxide solution, the pH after 44.9 mL of sodium hydroxide have been added is 8.71. This is calculated using the Henderson-Hasselbalch equation and taking into account the additional volume of sodium hydroxide added.

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The volume of 0.375 mL of 7.48x10-2 m perchloric acid can be neutralized with 115ml of 0.244m sodium hydroxide

To solve this problem, we need to calculate the number of moles of each substance first. For 7.48x10-2 m perchloric acid, the number of moles can be calculated using the molarity and the volume:
Moles of Perchloric Acid = (7.48x10-2 m) x (115 mL) = 0.00864 mol

To calculate the number of moles of sodium hydroxide, we can use the same method:
Moles of Sodium Hydroxide = (0.244 m) x (115 mL) = 0.0281 mol

Since both the perchloric acid and sodium hydroxide are in equal molar ratios, we know that 0.00864 mol of perchloric acid will be neutralized by 0.0281 mol of sodium hydroxide. To calculate the volume of the perchloric acid needed for this reaction, we can use the following equation:
Volume (mL) of Perchloric Acid = (0.0281 mol) / (7.48x10-2 m) = 0.375 mL

Therefore, 0.375 mL of 7.48x10-2 m perchloric acid can be neutralized with 115 mL of 0.244m sodium hydroxide.

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To distinguish between cyclohexane and 2-hexene, you can carry out the bromine water test. Chemical equation for the reaction is 2-hexene + Br2 (aq) -> 2,3-dibromohexane

This test is based on the fact that cyclohexane is an alkane and 2-hexene is an alkene. Alkenes readily react with bromine water due to the presence of a double bond, while alkanes do not react.

Add a few drops of bromine water to separate test tubes containing cyclohexane and 2-hexene.

Observe the color change in the test tubes.

Chemical equation for the reaction:

2-hexene + Br2 (aq) -> 2,3-dibromohexane

Upon reaction, the bromine water loses its color in the presence of 2-hexene, while it remains the same in the presence of cyclohexane.

This difference in color change will help you distinguish between the two compounds.

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