part a - identify the product of radioactive decay identify the product of radioactive decay and classify the given nuclear reactions accordingly. drag the appropriate items to their respective bins.

The stereochemistry on the basis of the fact that iodolactonization is normally an anti addition and it was determined experimentally that the ring junction is cis. is Option A.

Stereochemistry is a branch of chemistry that involves the study of different spatial arrangements of atoms within molecules. Stereochemistry is a systematic presentation of a particular field of science and technology and traditionally requires a brief history course.

Stereochemistry is the visualization of molecules in 3D. Before I learned stereochemistry, I had only studied the two-dimensional structure of molecules so it is very difficult for students. You can explore different ball-and-stick models of molecules for proper visualization in 3D. Stereoisomerism.

Certain substituted derivatives of cycloalkanes exhibit a type of isomerism called stereoisomerism. In this isomerism, two substances have the same molecular formula and composition but differ in the spatial arrangement of their atoms.

Learn more about Stereochemistry here:- https://brainly.com/question/13266152

#SPJ4

Answer:

To determine the factor by which the volume of a substance must be increased when the temperature is increased from 25oC to 50oC, we need to know the substance's coefficient of thermal expansion.

The coefficient of thermal expansion is a measure of how much a substance's volume will increase in response to a given temperature change.

Assuming that we have the coefficient of thermal expansion for the substance in question, we can use the following formula to calculate the factor by which the volume must be increased:

Factor = 1 + coefficient of thermal expansion * (change in temperature)

In this case, the change in temperature is 50oC - 25oC = 25oC. Therefore, the factor by which the volume must be increased is:

Factor = 1 + coefficient of thermal expansion * 25oC

The exact value of the factor will depend on the substance's coefficient of thermal expansion. In general, substances with a high coefficient of thermal expansion will have a larger increase in volume when the temperature is increased.

N2(g) + 3H2(g) 2NH3 is the reaction's balanced equation (g)

The equation for the reaction's equilibrium constant, k, is k = [NH3(g)]2 / [N2(g)].[H₂(g)]

The concentrations in the sample are in an equilibrium state. So, we may just utilize those in the computation.

0.184 mol/L= [NH3(g)]

0.551 mol/L= [N2(g)]

0.4 mol/L= [H2(g)]

Applying the equation, k = (0.184 mol/L)2 / ((0.551 mol/L) x (0.400 mol/L)3), yields k = 0.960 mol2 L2.

As a result, the reaction's equilibrium constant at 500 °C is 0.960 mol2 L2

To learn more about equilibrium click the link

https://brainly.com/question/517289

#SPJ1.

The chemical pair that will produce a buffer solution when dissolved in water is HNO2 and NaOH. (Option C)

A buffer solution refers to an aqueous solution which consists of a mixture of a weak acid and its conjugate base, or vice versa. A buffer solution is a solution whose pH only changes slightly when an acid or a base is added to it. For an acid-buffer solution, it consists of a weak acid and its conjugate base. For a basic-buffer solution, it consists of a weak base and its conjugate acid. The HNO2 and NaOH will form a buffer as it is a mixture of weak acid and its conjugate base.

Note: The question is incomplete. The complete question probably is: Which of the following chemical pairs produce a buffer solution when dissolved in water? A) NaOH and HBr B) NaCl and HCl C) HNO2 and NaOH D) NH3 and HCl.

Learn more about Buffer solution:

https://brainly.com/question/8676275

#SPJ4

It is a monovalent inorganic ion that belongs to the reactive nitrogen species and is called a nitrogen oxoanion.

What is ion ?

An ion with more than one atom is referred to as a polyatomic ion. One such ion is the nitrate ion! It has one nitrogen atom and three oxygen atoms.

As seen in the graphic accompanying this answer, it is an ion in which there is charge separation. The nitrate ion's Lewis structure, which complies with the octet rule, is represented in the diagrams.Nitrates are an ester family of nitric acid (HNO3) and alcohol molecules. By losing a proton from nitric acid, nitrate is a nitrogen oxoanion. main species found at pH 7.3.

To learn more about ion click here:

https://brainly.com/question/13692734

#SPJ4

The final velocity of particle B when it reaches the negative plate is 2.318×10^6 m/s.

According to the work-energy theorem work done by the particle is equal to an increase in kinetic energy

Given

Mass of particle A  is m(A)= 5×10^-30 kg

Charge on particle A q(A)= 1.6×10^-19 C

V1=40 volt and V2= -100 volt

Work done by particle A is  ∆E=q(A)(V1-V2).  

∆E=1.6×10^-19*×(40-(-100))=1.6×10^-19×140 jule

∆E=224×10^-19 joule

Let the velocity of particle A at the negative plate is v(A)

Kinetic energy of particle K.E=1/2×m(A)×v(A)^2

By the work-energy theorem ∆E=K.E

So.    1/2×5×10^-30×v(A)^2=224×10^-19

V(A)^2=8.96×10^12

V(A) = 2.993×10^6 m/s

The final velocity of particle A when it reaches the negative plate is 2.993×10^6 m/s

Now

Mass of partial B is m(B) =2.5×10^-29 kg

Charge of particle B is q(B)= 4.8×10^-19 C

Work done by particle B is ∆E= q(B)×(40-(-100)

∆E=4.8×10^-19×140 =672×10^-19 jule

Let the final velocity of a particle at the negative plate is v(B)

By applying the work energy theorem.

1/2×m(B)×v(B)^2= 672×10^-19

v(B)^2=537.6×10^10

V(B)=2.318×10^6 m/s

To learn more about kinetic and potential energy,

https://brainly.com/question/15764612

#SPJ4

The conjugate acid of H₂PO4 is H₃PO₄.

The correct option is D.

Conjugate acids are chemical species that are formed when a base accepts a proton.

A conjugate acid contains one more proton than the base from which it is formed.

Conjugate acids are derived from the Brønsted–Lowry acid–base theory, which states that an acid is a  chemical compound that donates a proton to a base.

The conjugate acid of H₂PO4⁻ will contain one more proton and a higher positive charge than H₂PO4⁻. Hence, the conjugate acid of H₂PO4⁻ is H₃PO₄.

Learn more about conjugate acids at: https://brainly.com/question/12584785

#SPJ1

FALSE, the isotope carbon-14 decays to nitrogen-14 over a half-life of 5,730 years. these isotopes could be used to determine the age of rocks formed early in the cenozoic era, approximately 60 million years ago.

Having the chemical symbol C and atomic number 6, carbon is an element with the meaning "coal" in Latin. It is nonmetallic and tetravalent, meaning that four of its atom's electrons may be used to create covalent chemical connections. The periodic table's group 14 is where it belongs. Only 0.025 percent of the crust of the Earth is made up of carbon. The bond sequence affects a bond's strength. Because shorter bonds have a higher bond strength than longer bonds, the higher the bond order, the stronger the bonds are. The bond order of carbon dioxide is 2, that of carbon monoxide is 3, and that of the carbonate ion is 1.33.

Learn more about carbon here:

https://brainly.com/question/22530423

#SPJ4

An electron from of the M shell occupying a hole in the K shell at 69 keV expelled as you move from the outside in to the inside will be moving to an energy levels with an ionization energy of 70 keV  -2 keV,

The minimal energy needed to ionize an atom is sufficient to eject an electron from its ground state. Ionization energy has a periodic trend that rises across the chemical elements form top to bottom as well as from left to right.

As you move from left to right along a period just on periodic table, the initial ionization energy often rises. This is because when nuclear charge rises, the outermost electron becomes more tightly connected to the nucleus.

to know more about ionization energy visit:

https://brainly.com/question/28385102

#SPJ4

When an atom's oxidation number rises, the reducing agent reduces the atom, and when it falls, the oxidising agent reduces the atom. The oxidising agent is the atom that is reduced, while the reducing agent is the atom that is oxidised.

For instance, the oxygen ion O2+ has an oxidation number of 2 because it can contribute two electrons, whereas the iron ion Fe3+ has an oxidation number of +3 because it can take up three electrons to establish a chemical bond.

Electrons are lost during oxidation. An rise in the substance's oxidation state results from the loss of negative charge. Fe atoms become oxidised to Fe2+ ions after losing two electrons.

Learn more about oxidation number refer

https://brainly.com/question/13182308

#SPJ4

total amount of energy required is= 132.6 + 717.9 + 45.42 = 896 kJ to convert 450g of liquid water from 38°C to water vapor at 125 C. The molar heat of vaporization (Hvap) of water is 40.79 kJ/mol. The specific heat for water is 4.184 J/g C, and for steam is 1.99 J/g C.

cslculation-heat energy required to raise the temp of liquid water to 100 C = 317 * 4.184 * 100 = 132632 J =132.6 kJ,mole of water = 317 / 18 = 17.6 mol,heat required for vaporization = 17.6 * 40.79 = 717.9 kJ,Heat required to raise the temp of water vapor to 172 C = 317 * 1.99 * 72 = 45420 J = 45.42 kJ, total heat required  = 132.6 + 717.9 + 45.42 = 896 kJ. The quantity of heat necessary to increase the temperature of one unit mass of a substance by one degree Celsius. The specific heat capacity of a substance is specified as the amount of heat (J) soaked up per unit mass (kg) when its temperature rises 1 K (or 1 °C). The specific heat capacity of a substance is typically calculated by monitoring the heat capacity of a specimen of the material, generally with a calorimeter, and trying to divide by the sample's mass. The average kinetic energy of each molecule increases as the substance heats up.

Learn more about specific heat here:

https://brainly.com/question/11297584

#SPJ4

Lewis structures are used to show the arrangement of electrons around the valence shell of atoms present in the molecules.

A Lewis dot structure is composed of dots and symbols of the elements. The Lewis structure shows the electrons present on the valence shells of atoms in molecules. We can easily deduce the number of valence electrons in a molecule by simply counting the number of electrons from the molecule.

The Lewis structure of NH₂Cl is clearly shown in the image attached. The lone pairs of electrons are shown by using dots while the bond pairs are shown by using a single dash.

Learn more about Lewis dot structure from the link given below.

https://brainly.com/question/29611367

#SPJ4

in general, the basic the leaving group, the reactive than carboxylic acid derivative is Acid chloride, Acid anhydride.

Carboxylic acid is a carboxylate gang organic compound. They are abundant and are also synthesised by humans. Carboxylic acids start to denature to form a carboxylate anion with the general formula R-COO-, that can form a variety of useful salts such as shampoos. The IUPAC name of a carboxylic acid is derived from the spelling of the parent alkane's lengthiest carbon chain that includes the carbon - carbon double bond by removing the final -e as well as adding the suffix -oic followed by the term "acid." The sequence is counted starting with the carboxyl group's carbon.

Learn more about Carboxylic acid here:

https://brainly.com/question/28167857

#SPJ4

the complete question is :

in general, the basic the leaving group, the reactive than carboxylic acid derivative. (select all that apply)

Acid chloride

Acid anhydride

Ester

Amide

The lewis structure of [tex]PF_3[/tex] shows that the central phosphorus atom has 1 nonbonding and 3 bonding electron pair(s)

Let us consider the Lewis Structure of [tex]PF_3[/tex]

Here, the central atom is phosphorus P.

We know, The atomic number of Phosphorus is 15.

The so the distribution will be like 2, 8, 5

Here, in the last orbit total of 5 electrons are present, so for completing the octet it needs 3 more electrons.

Hence, The phosphorus atom has 1 non-bonding and 3 bonding electron pairs with fluorine atoms.

For more questions on Lewis Structure

https://brainly.com/question/18369649

#SPJ4

the concentrations of the I-, IO3-, and H3AsO3 using m1v1=m2v2 is  2.2867 x 10^6, The initial concentration of [H+] in the solition for each experiment is 0.976 x 10^6, The rate of reaction is 2.7427 x 10^-

substance's concentration is the sum of solute in a provided amount of solution. Molarity is the amount of moles of solvent in one volume of water and is used to express concentrations. A solution's concentration is described as the quantity of solute present in a provided amount of solution. It can be stated as follows: Mass by a solution's mass percentage =mass of solutemass of solution 100 . The rate at which a chemical reaction occurs is defined as commensurate to an increase in the amount of a product per unit time and the reduce in the amount of a reactant per unit time. The rates of reaction could really vary greatly.

Learn more about concentration here:

https://brainly.com/question/10725862

#SPJ4

The universe's most prevalent mass-containing particles are neutrinos. Atomic nuclei emit neutrinos whenever they combine (as in the sun) or disintegrate (as in a nuclear reactor).

A particle is a neutrino. It is one of the so-called fundamental particles, which means that, at least as far as we are aware, it is not composed of any smaller parts. The electron, the most well-known fundamental particle (and the one driving the device you're reading this on right now), belongs to the same family as neutrinos. Neutrinos don't have any charge at all, in contrast to electrons which have a negative charge.

Additionally, neutrinos are exceedingly light and tiny. They have a small amount of mass. Of all the mass-containing subatomic particles, they are the lightest. They are the most abundant massive particle in the universe, and they are also quite common. Neutrinos originate from a variety of sources and are frequently the result of a process known as "decay," in which heavy particles transform into lighter ones.

To learn more about neutrinos. Please visit the below link.

https://brainly.com/question/27870530

#SPJ4

One can either conclude that the rope rotted quicker due to the presence of a higher concentration of salt in the ocean or that there is not enough information to make a conclusion. Options B and D.

From the available data in the table, it took the rope 10 years to rot in a lake water. Whereas, it took the rope 4 years to rot in an ocean water.

Also from the table, the average concentration of salt in the lake water is almost zero, whereas, the average concentration of salt in the ocean water is high.

Two things can be inferred from this reaction:

In order to accept the first inference, we will assume that all other factors have been examined and kept constant except the concentration of salt in the two water bodies. This will also include that the same size of rope was used in the two water bodies.

Without the assumptions made in the first inference, there is not enough information to arrive at a specific conclusion.

Thus, both B and D are plausible options.

More on rate of reactions can be found here: https://brainly.com/question/28566775

#SPJ1

Answer:

Explanation:

Quantitative properties are characteristics of a substance that can be measured using a numerical value. Examples of quantitative properties include mass, volume, density, and chemical concentration. These properties can be measured and compared using mathematical techniques and formulas.

Qualitative properties, on the other hand, are characteristics of a substance that cannot be measured using a numerical value. Examples of qualitative properties include color, odor, taste, and texture. These properties are typically described using words or phrases, and cannot be compared using mathematical techniques.

Quantitative and qualitative properties are both important for understanding the characteristics and behavior of a substance. Quantitative properties are useful for making precise measurements and predictions, while qualitative properties provide valuable information about the appearance and sensory properties of a substance. Together, these two types of properties help us to understand the nature of a substance and its behavior in different situations.

Answer:

The heat value can be calculated using the equation q = m * c * delta T, where q is the heat value, m is the mass of the iron sample, c is the specific heat of iron, and delta T is the change in temperature. In this case, q = 9.0 g * 0.44 J/g * (60-30) = 804 J.

The sign of q indicates whether heat is being absorbed or lost by the iron sample. In this case, since the temperature of the iron sample decreases from 60°C to 30°C, the sample loses heat and q is negative. Therefore, the heat value of the iron sample in this case is -804 J.

A 9.0 g sample of iron (specific heat= 0.44 J/g °C) heated to 60°C eventually cools to 30°C. 804 J  is the heat value. The sign of heat is negative which indicate energy is released.

Heat is the energy that moves through one thing to another if the temperatures are different. Heat passes from the hotter to the colder body when two bodies with differing temperatures are brought together. Typically, but not always, this energy transfer results in a rise inside the temperature of a colder body and a fall inside the temperature of a hotter body.

By transitioning through one physical state (and phase) to the other, such as melting from such a solid to a liquid, sublimation from either a solid to a vapour, boiling from such a liquid to a vapour, or shifting through one stable state to another, a substance can absorb heat without increasing in temperature.

q = m × c × ΔT

q = heat

m = mass of the iron sample

c =specific heat of iron

Δ T= change in temperature

q = 9.0 g×0.44 J/g × (60-30) = 804 J

heat = -804 J.

Therefore, a 9.0 g sample of iron (specific heat= 0.44 J/g °C) heated to 60°C eventually cools to 30°C. 804 J  is the heat value. The sign of heat is negative which indicate energy is released.

To know more about heat, here:

https://brainly.com/question/29548185

#SPJ2

The ΔH of the reaction of the formation of N₂O₄ is equal to - 90 KJ.

Hess's law of constant heat summation can be defined as the total enthalpy change while the complete course of a chemical reaction independent of the sequence of steps.

Given, the reactions can be represented as:

N₂ (g) + O₂(g) →  NO                   }   ×1                       ΔH = + 90 KJ

NO (g) + 1/2 O₂ (g)  →  NO₂ (g)    }  × 2                     ΔH = -56 KJ

2NO₂ (g) →  N₂O₄ (g)                   }   × 1                 ΔH = - 58 KJ

The overall reaction of the formation of  N₂O₄ (g)  can be obtained as:

N₂ (g)  +2 O ₂  (g)  →  N₂O₄ (g)

ΔH = 1 × 90  + 2 ×(-56)  + 2 × (-58)

ΔH = = - 90 KJ

Learn more about Hess's law, here:

brainly.com/question/14561923

#SPJ1

12 electrons are transferred in this oxidation–reduction reaction.

What is oxidation-reduction reaction?

Reduction-oxidation is referred to as redox, and a redox reaction is one in which both a reduction reaction and an oxidation reaction occur at the same time. Additionally, it is an acronym for an oxidation-reduction reaction. Let's first talk about each of these two elements independently before returning to how they interact to form a complete redox reaction.

The balanced reaction is

4 Fe (s) + 3 O2 —> 2 Fe2O3 (s)

Oxidation state of Fe changes from 0 to +3 and there are 4 such Fe.

So, it loses 4*3 = 12 electrons

Oxidation state of Oxygen changes from 0 to -2 and there are 6 such Oxygen.

So, it gains 6*2 = 12 electrons

Hence, we can say that 12 electrons are transferred.

To learn more about oxidation-reduction reaction from the given link.

https://brainly.com/question/13892498

#SPJ4

Complete question:

Rust (Fe2O3) forms on abandoned cars such as the one in this photo through a series of reactions between iron in the car and oxygen in the atmosphere.

The unbalanced chemical equation for this reaction is

Fe(s) + O2(g) –> Fe2O3(s)

How many electrons are transferred in this oxidation–reduction reaction?________ electrons

One fluorine atom is added to the phosphorus trifluoride molecule to create this molecule. The molecule has a pyramidal form by nature. In this instance, the bond angle for F-P-F is 109 degrees.

What is nf3's bond angle?

Similar to ammonia, the molecule possesses a trigonal pyramidal structure. The very electronegative fluorines pull the electrons in the N-F bonds towards themselves, lowering interelectronic repulsions, and reducing the bond angle from 107° in ammonia to 101.9° in NF3. As a result, the NF3 "umbrella" closes up.

that has a higher bond angle NF3 or NCl3?

The N-F bond would have a stronger p character than the N-H bond because fluorine is more electronegative than hydrogen. Large bond angles result from more strong character. As a result, NH3 has a larger bond angle than NF3. Now think about NCl3

To know more about f-a-f bond angles visit;

https://brainly.com/question/2286566

#SPJ4

At very high pressures, the molecular volume of the gas particles is significant.At moderately high pressures there are significant intermolecular attractions is the statements that correctly account for this given behavior.

An equation of states is PV = nRT. Three variables are P, V, and T. They are variables because they indicate the pressure, volume, and temperature of a gas in a certain condition as well as other physical characteristics. The ideal gas constant (R) is a constant that may be found in chemical literature, and the number of moles (n) may be maintained constant. Moles (n) may be set to PV / RT as follows: n = PV / RT. T / V ratio becomes important because pressure (P), which is directly proportional to T and indirectly proportional to V, depends on it.Volume (V) is a function of T/P, with V being directly proportional to T and indirectly proportional to P. PV is a necessary condition for temperature (T), which is directly proportional to variations in both P and V.

To know more about ideal gas constant  please click on the link brainly.com/question/3961783

#SPJ4

At STP, the volume of one mole of any gas is 22.4 L. As per the given reaction, one mole or 22.4 L of Cl₂ gas gives one mole. Thus, 22.4L of  Cl₂ gives 21 L of I₂ gas.

The molar volume of a substance is the space occupied by one mole of that substance. Each chemical has a molecular weight of 22.4 L when measured under standard temperature and pressure conditions (STP).

At STP, a mole of Cl2 gas holds 22.4 L, while a mole of I2 also contains 22.4 L. According to the reaction, a mole of Cl2 yields a mole of L2. As a result, both are contributing equally to this reaction.

As a result, at STP, 21 L Cl₂ reacts to produce 22.4 L₂.

To find more on molar volume, refer here:

brainly.com/question/4172228

#SPJ1

The sequence of amino acids in a polypeptide chain is the most basic level of protein structure, known as primary structure. Insulin, for example, has two polypeptide chains. Each chain has its own set of amino acids that are assembled in a specific order.

Secondary structure is the next level of protein structure and refers to local folded structures that form within a polypeptide as a result of interactions between backbone atoms.The helix and the pleated sheet are the two most common types of secondary structures.

A polypeptide's overall three-dimensional structure is referred to as its tertiary structure. The tertiary structure of the protein is primarily due to interactions between the R groups of the amino acids that comprise it. Hydrogen bonding, ionic bonding, dipole-dipole interactions, and London dispersion forces are all examples of R group interactions that contribute to tertiary structure. R groups with like charges, for example, repel one another, whereas those with opposite charges can form an ionic bond.

learn more about protein here

https://brainly.in/question/25310342

#SPJ4

The darker surfaces receive high temperature, and less light, the lighter surface receives low temperature and more light.

What is temperature?

Temperature is a unit of measurement that can be expressed on a variety of scales, including Fahrenheit and Celsius. Temperature shows the direction of the spontaneous movement of heat energy, i.e., from a hotter body (one with a higher temperature) to a colder body (one at a lower temperature).

What is Dark surfaces ?

Black surfaces serve as effective heat radiators and absorbers. Any object's color is determined by the light it reflects. If an object reflects all the light that strikes it, it is said to be white. If an object reflects no or very little light and absorbs practically all of the light, it is said to be black.

Blocking the red, blue, and green lights produces cyan; blocking the green, red, and blue lights produces magenta; and blocking the blue, red, and green lights produces yellow. By switching off several light fixtures, you may create a similar effect.

Therefore, the darker surfaces receive high temperature, and less light, the lighter surface receives low temperature and more light.

Learn more about temperature from the given link.

https://brainly.com/question/25677592

#SPJ1

The final volume of the solution is  666.7 mL.

We know that we can be able to obtain the volume of the solution by applying the formula for dilution. When we talk about dilution we are referring to the volume of the water that we have to add to the solution.

Then we have;

Initial volume V1 = 20.0 mL

Final volume V2 = ?

Initial concentration C1 =  1.40 M

Final concentration C2 = 0.0420 M

Then we have

C1V1 = C2V2

V2 = C1V1 /C2

V2 = 20.0 mL * 1.40 M/0.0420 M

V2 = 666.7 mL

Learn more about dilution:https://brainly.com/question/28997625

#SPJ1

If the nuclide is above the valley of stability, the n/Z ratio is too high and it will undergo β decay to reach the valley of stability.

If the nuclide is below the valley of stability, the n/Z ratio is too low and it will undergo β+ decay or α decay to reach the valley of stability.

The nuclear reaction is one that changes the structure of the nucleus of an atom. The atomic numbers and mass numbers in a nuclear equation must be balanced. Protons and neutrons are made up of quarks. The two most common modes of natural radioactivity are alpha decay and beta decay. The nuclear disintegration process that emits alpha particles is called alpha decay.  All nuclei with 84 or more protons are radioactive, and elements with less than 84 protons have both stable and unstable isotopes. All of these elements can go through nuclear changes and turn into different elements.

To learn more about Radioactive Decay please visit:

https://brainly.com/question/9932896

#SPJ4

UV light is the most popular non-destructive visualization technique for TLC plates. stains from thin layer chromatography.

To see TLC findings for colorless substances, a visualizing approach is required. It will provide a means of seeing these chemicals as well as a Single alkenes do not show up very well on TLC under UV, even when markers are applied, hence this procedure is known as staining the TLC plate. Offer a stain that might be utilized to help a TLC viewer see your goods. Normally, a UV (Ultraviolet) lamp is required to see the various spots, but if the compounds are brightly colored, It is possible to conduct both qualitative and quantitative analyses using thin layer chromatography. Excellent wettability for accurate colorization outcomes.

to know more about TLC plates please visit.

https://brainly.com/question/17562109

#SPJ4

The pH in each case depends on the relative amounts of acid and base present.

a) Before the addition of HBr:

Number of moles = Mass of substance / Mass of one mole

Number of moles of C5H5N = 25/1000 L × 0.150 M = 0.00375 moles

pOH = -log[0.00375 M]

pOH = 2.42

pH = 14 - 2.42

pH== 11.58

b) After the addition of 12.5 mL of HBr:

Since the reaction is 1:1

Number of moles of HBr = 12.5/1000 L × 0.150 M = 0.00375 moles

The HBr is the limiting reactant

Amount of excess acid = 0.0045 M - 0.00375 = 0.00075 moles

Total volume of solution = 25mL + 12.5 mL = 37.5mL or 0.0375L

molarity of excess H+ = 0.000075 moles / 0.0375 L = 0.002 M

pH = - log[0.002M]

pH = 2.69.

c) After the addition of 19.0 mL of HBr:

Number of moles of acid = 19/1000  × 0.150 M = 0.00285 moles

Number of moles of excess acid =  0.0045 moles  - 0.00285 moles = 0.000165 moles

Total volume of solution =  19.0 mL +  25.0 mL = 44mL or 0.044 L

Molarity of excess acid = 0.00018 moles/ 0.044 L = 0.00409 M

pH = -log[0.00409 M]

pH== 11.58

d) After the addition of 25.0 mL of HBr:

Number of moles of acid = 25/1000  × 0.150 M = 0.00375 moles

We have an equal number of acids and bases hence pH=11.65

e) After the addition of 33.0 mL of HBr:

Number of moles of acid = 33/1000  × 0.150 M =0.00495 moles

We can see that the base is the limiting reactant.

Number of moles of excess base = 0.00495 moles

Total volume of solution = 33 mL + 25 mL = 58mL or 0.058 L

Molarity of excess base = 0.00162 moles/0.058 L = 0.027 M

pOH = -log[ 0.027 M]

pOH = 1.56

pH = 14 - 1.56

pH- = 12.44

To know more about pH calculation:

https://brainly.com/question/15356078

#SPJ4