All of the following compounds can react as acids. Without using a table of acidities, rank them in order of increasing acidity. Explain your ranking. a. CH3CH2SO3H b. CH3CH OH c. CH3CH2COOH d. CH3CHCICOOH e. CICH CH2COOH

Heating a carboxylic acid with a primary amine forms a secondary amide and water.

When heating a carboxylic acid with a primary amine, the organic product formed, along with water, is a secondary amide. This reaction is an example of amidation, where the carboxyl group (-COOH) of the acid reacts with the amine group (-NH2) from the primary amine, resulting in the formation of a secondary amide and a molecule of water as a by-product. The process is important in the formation of peptides and proteins, where similar reactions link amino acids together.

Explanation:

When the water droplets are placed in oily surface, oil being non-polar, thus there will not be adhesive force between water and oil.

Thus, surface tension is the factor which is responsible for shape of the water droplets to be spherical. The water molecules are pulled into the spherical shape by the action of the cohesive forces which is acting on the surface layer. As, the medium is totally different outside, the water molecules tend to get the minimum area and thus, forming spherical droplets.

Answer:

True

Explanation:

*For polar and associated substances, methods based on four should be used  four or more parameters, like analytical equation of state

*The term "analytical equation of state" implies that the function

It contains powers of v not greater than four.

*Most expressions are of the cubic type and are grouped into

the so-called cubic equations of state.

*Cubic EoS calls are very popular in simulation of

processes due to its robustness and its simple extension to mixtures.

*They are based on the van der Waals state equation of more than

100 years.

Answer:

[tex](\rho*Q)/(\mu*h)[/tex]

Explanation:

First, we need to establish the unit of each variable:  

To eliminate [tex]m^3[/tex] we need to multiply Q by [tex]\rho[/tex]. Then to eliminate kg we divide [tex]\rho[/tex] by [tex]\mu[/tex]. Finally, multiply [tex]\mu[/tex] by h we can let the constant dimensionless.

Answer:

[tex]1.64x10^-^1^7 J[/tex]

Explanation:

Due to you know the velocity of the electron, the only thing that you need to do is used the Newtonian kinetic energy formula.  The kinetic energy is defined as the work needed by motion body of a given mass to accelerate from rest to its know velocity:

[tex]KE=1/2mv^2=[kg*(m/s)^2]=[J][/tex]

[tex]m_e_- =9.1093835x10^-^3^1 kg [/tex]

[tex]KE=9.11x10^-^3^1 kg*(6.00x10^6 m/s)^2=1.64x10^-^1^7 J[/tex]

Answer:

A solvent is a chemical substance that has the ability to dissolve other chemical compounds, called solute, to form a solution.                

Solvents can be polar and non-polar in nature.

In general, polar solvents dissolve only polar solute molecules and non-polar solvents dissolve only non-polar solute molecules.

Highly polar solute molecule such as ionic compounds like NaCl and sugars, dissolve only in highly polar solvents with a large dielectric constant like water.

Therefore, because of the high dielectric constant of water, ionic compounds can be easily separated and dispersed.

Answer:

[tex]Q=\frac {[Fe^{2+}]^2[Zn^{2+}]}{[Fe^{3+}]^2}[/tex]

Explanation:

The reaction quotient of an equilibrium reaction measures relative amounts of the products and the reactants present during the course of the reaction at  particular point in the time.

It is the ratio of the concentration of the products and the reactants each raised to their stoichiometric coefficients. The conecntration of the liquid and the gaseous species does not change and thus is not written in the expression.

Thus, for the reaction:

[tex]2Fe^{3+}_{(aq)}+Zn_{(s)}\rightleftharpoons 2Fe^{2+}_{(aq)}+Zn^{2+}_{(aq)}[/tex]

The expression is:

[tex]Q=\frac {[Fe^{2+}]^2[Zn^{2+}]}{[Fe^{3+}]^2}[/tex]

Answer:

[tex]CaCl_2[/tex]

Explanation:

Calcium is the element of the group 2 and period 4 which means that the valence electronic configuration is [tex][Ar]4s^2[/tex].

Chlorine is the element of the group 17 and period 3 which means that the valence electronic configuration is [tex][Ne]3s^23p^5[/tex].

Thus, calcium losses 2 electrons to 2 atoms of chlorine and these 2 atoms of chlorine accepts each electron to form ionic bond. This is done in order that the octet of the atoms are complete and they become stable.

Ca         Cl

2            1

Cross multiplying the valency, We get, [tex]CaCl_2[/tex]

Thus, the formula of calcium chloride is [tex]CaCl_2[/tex].

Calcium Chloride, with the formula CaCl2, is composed of one calcium (Ca2+) ion and two chloride (Cl-) ions to ensure electrical neutrality.

The compound Calcium Chloride is formed by the elements calcium (Ca) and Chloride (Cl). From the periodic table, we can see that calcium (Ca) forms +2 ions and Chloride (Cl) forms -1 ions. As compounds must be electrically neutral, the formula of an ionic compound represents the simplest ratio of the numbers of ions necessary to balance out the charges. Thus, for every calcium ion, we need two chloride ions to balance out the charges. So the formula for this compound is CaCl2.

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Answer :

(a) The rate of reaction is, second order reaction.

(b) The rate of reaction is, zero order reaction.

Explanation :

Rate of reaction : It is defined as the rate of change in concentration of reactant or product with respect to time.

Order of reaction : It is defined as the sum of the exponents or powers to which the molar concentration in the rate law equation are raised to express the observed rate of reaction.

The order of reaction depends on the power of reactant concentration.

(a) The given rate expression is,

[tex]Rate=k[NO_2]^2[/tex]

From this expression we conclude that the power of concentration of reactant [tex]NO_2[/tex] is 2.  

That means it is a second order reaction.

(b) The given rate expression is,

[tex]Rate=k[/tex]

From this expression we conclude that the rate of reaction is equal to rate constant.

That means it is a zero order reaction.

Answer: The number of moles of ammonium nitrate is 0.004 moles.

Explanation:

To calculate the number of moles for given molarity, we use the equation:

[tex]\text{Molarity of the solution}=\frac{\text{Moles of solute}\times 1000}{\text{Volume of solution (in mL)}}[/tex]

We are given:

Molarity of [tex]NH_4NO_3[/tex] solution = 0.125 M

Volume of solution = 32.5 mL

Putting values in above equation, we get:

[tex]0.125M=\frac{\text{Moles of }NH_4NO_3\times 1000}{32.5mL}\\\\\text{Moles of }NH_4NO_3=0.004mol[/tex]

Hence, the number of moles of ammonium nitrate is 0.004 moles.

Answer : The moles of Ne gas are 46.25 moles.

Explanation :

using ideal gas equation

[tex]PV=nRT[/tex]

where,

P = pressure of gas = 45 atm

V = volume of gas = 24.3 L

T = temperature of gas = [tex]15.0^oC=273+15.0=288K[/tex]

R = gas constant = 0.0821 L.atm/mole.K

n = moles of gas = ?

Now put all the given values in the ideal gas equation, we get:

[tex](45atm)\times (24.3L)=n\times (0.0821L.atm/mole.K)\times (288K)[/tex]

[tex]n=46.25mole[/tex]

Therefore, the moles of Ne gas are 46.25 moles.

Answer:

0.14 M

Explanation:

To determinate the concentration of a new solution, we can use the equation below:

C1xV1 = C2xV2

Where C is the concentration, and V the volume, 1 represents the initial solution, and 2 the final one. So, first, the initial concentration is 1.50 M, the initial volume is 55.0 mL and the final volume is 278 mL

1.50x55.0 = C2x278

C2 = 0.30 M

The portion of 139 mL will be the same concentration because it wasn't diluted or evaporated. The final volume will be the volume of the initial solution plus the volume of water added, V2 = 139 + 155 = 294 mL

Then,

0.30x139 = C2x294

C2 = 0.14 M

Answer:

The final concentration is 0.140 M

Explanation:

n₁=M₁.V₁ (First equation)

n₁=1.50 M

V₁=55 mL

M₂=n₂/V₂ (Second Equation)

V₂=278 mL

n₁=n₂

M₂=M₁.(V₁/V₂) (Third Equation)

n₃=M₃.V₃ (Forth Equation)

V₃=139 mL

M₃=M₂

n₃=M₁.(V₁/V₂).V₃ (Forth Equation)

M₄=n₄/V₄ (Fifth Equation)

n₄=n₃

M₄=M₁.(V₁/V₂).(V₃/V₄) (Sixth equation)

V₄=V₃+155 mL (Seventh Equation)

M₄=M₁.(V₁/V₂).(V₃/(V₃+155 mL))

M₄=1.50 M . (55mL / 278 mL) . ((139mL)/(139mL+155mL))

M₄=1.50 M . (55mL / 278 mL) . (139mL/294mL)

M₄=0.140 M

Answer:

Molecular weight of the compound = 372.13 g/mol

Explanation:

Depression in freezing point is related with molality of the solution as:

[tex]\Delta T_f = K_f \times m[/tex]

Where,

[tex]\Delta T_f[/tex] = Depression in freezing point

[tex]K_f[/tex] = Molal depression constant

m = Molality

[tex]\Delta T_f = K_f \times m[/tex]

[tex]1.33 = 5.12 \times m[/tex]

m = 0.26

Molality = [tex]\frac{Moles\ of\ solute}{Mass\ of\ solvent\ in\ kg}[/tex]

Mass of solvent (toluene) = 15.0 g = 0.015 kg

[tex]0.26 = \frac{Mole\ of\ compound}{0.015}[/tex]

Moles of compound = 0.015 × 0.26 = 0.00389 mol

[tex]Mol = \frac{Mass\ in\ g}{Molecular\ weight}[/tex]

Mass of the compound = 1.450 g

[tex]Molecular\ weight = \frac{Mass\ in\ g}{Moles}[/tex]

Molecular weight = [tex]\frac{1.450}{0.00389} = 372.13\ g/mol[/tex]

Answer:

497.01 seconds will it take light to move a distance of [tex]1.49\times 10^8 km [/tex]from the Sun to the Earth.

Explanation:

Speed of the light = 299,792,458 m/s

Time taken by the light to cover [tex]1.49\times 10^8 [/tex] kilometer = T

[tex]1.49\times 10^8km=1.49\times 10^{11} m[/tex]

Speed=[tex]\frac{Distance}{Time}[/tex]

[tex] 299,792,458 m/s=\frac{1.49\times 10^{11} m}{T}[/tex]

[tex]T=497.01 seconds[/tex]

497.01 seconds will it take light to move a distance of [tex]1.49\times 10^8 km [/tex]from the Sun to the Earth.

To determine how long light takes to travel from the Sun to the Earth at a speed of 299,792,458 m/s for a distance of 1.49 x 10^8 km, convert the distance to meters and divide by the speed of light. The result is approximately 497 seconds.

If light moves at a speed of 299,792,458 m/s, and we want to determine how long it will take light to travel a distance of 1.49 x 108 km from the Sun to the Earth, we must first convert the distance to meters (since the speed of light is given in meters per second). To do this, we multiply by 1,000 (since 1 km = 1,000 m), yielding a distance of 1.49 x 1011 m.

To find the time in seconds, we divide the distance by the speed of light, which gives us:

Time (seconds) = Distance (m) / Speed of light (m/s) = 1.49 x 1011 m / 299,792,458 m/s

Performing the calculation yields approximately 497 seconds, which is the time it takes for light to travel from the Sun to the Earth with the given information. We use the same number of significant figures as presented in the distance measurement, which in this case is two (1.49).

The molar heat of vaporization of substance X can be determined using the Clausius-Clapeyron equation. The molar heat of vaporization of substance X is -61.78 kJ/mol.

The molar heat of vaporization of substance X can be determined using the Clausius-Clapeyron equation. The equation is given by:

ln(P₂/P₁) = -(ΔHvap/R)((1/T₂) - (1/T₁))

We can solve for ΔHvap by substituting the values given: P₁ = 100 mm Hg, T₁ = 1080 °C (or 1353 K), P₂ = 600 mm Hg, and T₂ = 1220 °C (or 1493 K).

ln(600/100) = -(ΔHvap/8.314)((1/1493) - (1/1353))

Solving for ΔHvap gives us a value of -61.78 kJ/mol. Therefore, the molar heat of vaporization of substance X is -61.78 kJ/mol.

Answer:

hhh

Explanation:

Pyranose is collective term for the saccharides which have chemical structure which includes six-membered ring that consists of one oxygen atom and five carbon atoms.

Furanose is collective term for carbohydrates which have chemical structure which includes five-membered ring system that consists of one oxygen atom and four carbon atoms.

Glucose exists both in pyranose and furanose form. It's structure is shown in image.

Answer:

The first solution has a final protein concentration of 0.0002 mg/ml.

To prepare the second solution, you have to take 56.25 ml of the stock solution 8 mg/ml and to add 43.75 ml of water.

Explanation:

For this kind of dilution problems is very useful the following equation:

Where Cc and Vc are the concentration and volume of the more concentrated solution respectively, whereas Cd and Vc are the concentration and volume of the diluted concentration. If you know three of these four parameters, you can calculate the missing parameter.

For the first solution, you have the volume (0.200 ml) and concentration (1 mg/ml) of the more concentrated solution, and the volume of the diluted soluted is implied (final volume= 0.2 ml + 0.8 ml= 1 ml). Then,

Cc x Vc=Cd x Vd

0.200 ml x 1 mg/ml= Cd x 1 ml

⇒ Cd= [tex]\frac{0.200 ml x 1mg/ml}{1 ml}[/tex] = 2 x 10⁻⁴ mg/ml= 0.0002 mg/ml

For the second solution, yo have the volume of the diluted solution (100 ml), the concentration of the diluted solution (4.5 mg/ml) and the concentration of the concentratesd solution (8 mg/ml). Then,

Cc x Vc= Cd x Vd

8 mg/ml x Vc= 100 ml x 4.5 mg/ml

⇒ Vc= [tex]\frac{100 ml x 4.5 mg/ml}{8 mg/ml}[/tex]= 56.25 ml

Thus, you have to take 56.25 ml of the more concentrated solution and to add the remaining volume of water to reach a final volume of 100 ml (100-56.25 ml= 43.75 ml)

Answer:

a) D = 33.44 Lbmol/h

⇒ B = 62.56 Lbmol/h

b) D = 16.848 Kmol/h

⇒ B = 28.152 Kmol/h

Explanation:

global balance:

∴ F = 100 Lbmol/h

balance per component:

A: 0.4*F = 0.9*D + 0.1*B = 0.4*100 = 40 Lbmol/h..............(2)

B: 0.6*F = 0.1*D + 0.9*B = 0.6*100 = 60 Lbmol/h..............(3)

from (2):

⇒ 0.9*D = 40 - 0.1*B

⇒ D = ( 40 - 0.1*B ) / 0.9............(4)

(4) in (3):

⇒ 0.1*((40-0.1*B)/0.9) + 0.9*B = 60

⇒ B = 62.56 Lbmol/h............(5)

(5) in (1):

⇒ D = 100 - B

⇒ D = 37.44 Lbmol/h

∴ Lbmol = 0.45 Kmol

⇒ B = 62.56 Lbmol/h * ( 0.45 Kmol/ Lbmol ) = 28.152 Kmol/h

⇒ D = 37.44 Lbmol/h * ( 0.45 Kmol/h ) = 16.848 Kmol/h

Answer:

The density of carbon dioxide is 1,86 g/L

Explanation:

The global reaction is:

2 HCl (aq)+ CaCO₃ (s) → CaCl₂(aq)+ H₂O(l)+ CO₂(g)

To obtain density it is necessary to obtain calcium carbonate moles -with molar mass of CaCo₃ = 100,09 g/mol- that are the same than CO₂ moles. Then, this moles must be converted to grams -CO₂ weights 44,01 g/mol- and, with the given liters (225 L) will be possible to know density, thus:

1004,0g × 95,0% = 953,8 g of CaCO₃

953,8 g of CaCO₃ ×[tex]\frac{1 mol}{100,09 g}[/tex] =

9,53 CaCO₃ moles ≡ CO₂ moles

9,53 CO₂ moles ×[tex]\frac{44,01 g}{1 mol}[/tex] = 419,4 g of CO₂

Thus, density of Carbon dioxide is:

[tex]\frac{419,4 g}{225 L}[/tex] = 1,86 g/L

I hope it helps!

Final answer:

To find the density of carbon dioxide, first calculate the mass of calcium carbonate used. Next, use the molar mass of CaCO3 to calculate the number of moles. Finally, calculate the density of CO2 using the mass and volume.

Explanation:

To find the density of carbon dioxide, we need to calculate the mass of carbon dioxide produced. From the given information, we know that a 1004.0g sample of calcium carbonate that is 95.0% pure gives 2.25L of CO2 at STP when reacted with an excess of hydrochloric acid. First, we calculate the mass of calcium carbonate used:

Mass of CaCO3 = 1004.0g * 0.95 = 954.8g

Next, we use the molar mass of CaCO3 (100.09 g/mol) to calculate the number of moles:

Moles of CaCO3 = 954.8g / 100.09 g/mol = 9.537 mol

According to the balanced chemical equation:

CaCO3 + 2HCl -> CaCl2 + CO2 + H2O

1 mole of CaCO3 produces 1 mole of CO2. Therefore, the number of moles of CO2 produced is also 9.537 mol.

Finally, we can calculate the density of CO2:

Density = Mass / Volume

Density = 9.537 mol * 44.01 g/mol / 2.25 L = 188.70 g/L

Answer: The mass of chlorine gas is 4.54 grams.

Explanation:

To calculate the mass of the gas, we use the equation given by ideal gas equation:

[tex]PV=nRT[/tex]

Or,

[tex]PV=\frac{m}{M}RT[/tex]

where,

P = pressure of the gas = 98.7 kPa

V = Volume of gas = 3.34 L

m = given mass of chlorine gas = ?

M = Molar mass of chlorine gas = 35.45 g/mol

R = Gas constant = [tex]8.31\text{ L kPa }mol^{-1}K^{-1}[/tex]

T = Temperature of the gas = [tex]37^oC=[37+273]=310K[/tex]

Putting values in above equation, we get:

[tex]98.7kPa\times 3.34L=\frac{m}{35.45g/mol}\times 8.31\text{ L kPa }mol^{-1}K^{-1}\times 310K\\\\m=4.54g[/tex]

Hence, the mass of chlorine gas is 4.54 grams.

Answer:

To maintain a pH value of 8.8 in a particular solution the best option is Tris or boric acid.

Explanation:

To decide a good acid/conjugate base pair it is necessary to know the pKa of the acids because every buffer has an optimal effective range due to pH = pKa ± 1. The closer the working pH is to the acid pKa, the buffer will be more effective. Below is the list of the pKa of the different option.

Acetic acid: pKa = 4.76

Boric acid: pKa1 = 9.24 pKa2 = 12.74 pKa3 = 13.80

Ascorbic acid: pKa1 = 4.17 pKa2 = 11.57

Tris:  pKa = 8.06

Acetic and Ascorbic acid are too far from the range of 8.8. Thus the best options are boric acid or Tris. To define between these two it is necessary to consider other factors like interaction between components of the solution and the ionic strength required.

Answer:

D. the forward reaction will have a lower activation energy than the reverse reaction.

Explanation:

An exothermic reaction is one which is accompanied by the release of heat energy. In this case the products have a lower energy than that of the reactants.

Activation energy is the minimum amount of energy required to initial or start a chemical reaction. In exothermic reactions, the reactants are at a higher energy (relative to the products) to begin with. Hence, they would require a lower activation energy to overcome the energy barrier in order to form the products.

The correct option is D. the forward reaction will have a lower activation energy than the reverse reaction.

In an exothermic reaction, energy is released as the reaction proceeds from reactants to products. This means that the products are at a lower energy state than the reactants. The activation energy for a reaction is the minimum amount of energy that the reactants must possess for the reaction to occur. Since energy is released during the reaction, the energy level of the products is lower than that of the reactants, and consequently, the activation energy for the reverse reaction (products going back to reactants) is higher than that for the forward reaction.

 Let's analyze each option:

A. The forward reaction is slower than the reverse reaction - This statement is not necessarily true for exothermic reactions. The rate of a reaction is determined by the activation energy and the concentration of reactants, among other factors.

 B. The reaction rate will speed up with time - This statement is not generally true. The rate of a reaction can change with time depending on various factors such as the concentration of reactants, temperature, and the presence of catalysts. However, for a simple exothermic reaction, the rate may slow down over time as the concentration of reactants decreases.

 C. The collision energy of the reactants will be greater than that of the products - This statement is true for an exothermic reaction because the reactants have more energy than the products, and the excess energy is released during the reaction.

 D. The forward reaction will have a lower activation energy than the reverse reaction - This statement is correct for an exothermic reaction. The products are at a lower energy state than the reactants, so the energy barrier for the reverse reaction is higher.

 E. The activation energy will change as the reaction progresses - This statement is not accurate in a simple sense. The activation energy is a characteristic of the reaction itself and does not change as the reaction progresses. However, the presence of intermediates or changes in reaction conditions can affect the observed activation energy.

Therefore, the correct answer is D, as it accurately describes the relationship between activation energies in an exothermic reaction.

Answer:

The molecular weight of the acid is 60.05 g/mol

Explanation:

Let's state the balanced chemical equation to represent the neutralization reaction:

NaOH + HAc → NaAc + H2O

where HAc is the representation of the monoprotic acid. As we can see, the relationship between the base and the acid is 1:1, that is 1 mole of NaOH reacts with 1 mole of the monoprotic acid HAc. So, let's calculate the moles of NaOH that where present in the 88.81 mL aliquot used to neutralize the acid:

1000 mL ---- 0.75 moles of NaOH

88.81 mL --- x = (88.81 mL × 0.75 moles)/1000 mL = 0.0666075 moles NaOH

As we stated before, 1 mole of NaOH will react with 1 mole of HAc, so 0.0666075 moles of NaOH will reacted with 0.0666075 moles of the acid. Having said that, because we already know the mass of the acid, we are able to determine the molecular weight of it:

0.0666075 moles of HAc ---- 4.00 g

1 mole of HAc ---- x = (1 mole × 4.00 g)/0.0666075 moles = 60.05 g/mole

Answer:

1.728 mol /(L*min)

Explanation:

Hello,

In the attached photo, you'll find the numerical procedure for your question.

- Take into account that the negative sign is eligible for reagents and positive for products.

Best regards!

Answer:

Hydrogen bonding

Explanation:

As a rule of thumb, "likes dissolve like", meaning polar solutes dissolve in polar solvents and nonpolar solutes in nonpolar solvents. In this case, water is polar (dipolar moment = 1.85 Debye) dissolves methanol which is also polar (dipolar moment = 1.69 Debye). Besides being dipoles, both molecules have atoms of Hydrogen with a covalent bond to more electronegative atoms of Oxygen. When this happens, stronger dipole-dipole interactions appear known as Hydrogen bonding. There is an electrostatic attraction between H (positive charge density) and O (negative charge density).

Answer: The given number in scientific notation is [tex]1.044\times 10^{-7}[/tex]

Explanation:

Scientific notation is the notation where a number is expressed in the decimal form. This means that the number is always written in the power of 10 form. The numerical digit lies between 0.1.... to 9.9.....

If the decimal is shifting to right side, the power of 10 is negative and if the decimal is shifting to left side, the power of 10 is positive.

We are given:

A number having value = 0.00000010445

Converting this into scientific notation, we get:

As, the decimal is shifting to right side, the power of 10 will be negative.

[tex]\Rightarrow 0.00000010445=1.044\times 10^{-7}[/tex]

Hence, the given number in scientific notation is [tex]1.044\times 10^{-7}[/tex]

Explanation:

Length of trash cans = l = 4 feet

Breadth of trash cans =  b = 4 feet

Height of trash cans =  h = 30 inches = 2.5 feet

1 inches = 0.0833333 feet

Capacity of trash can = Volume of the rectangular trash can = V

V = l × b × h

[tex]V=4 feet\times 4 feet \times  2.5 feet= 40 feet^3[/tex]

a) [tex]1 feet^3=7.48052 gallons[/tex]

[tex]V=40 feet^3=40\times 7.48052 gallons=299.221 gallons[/tex]

b) Density of water at 4°C = 1 kg /L

1 metric tonne of water = 264.17 gallons of water

[tex]V=299.221 gallons=\frac{299.221}{264.17}[/tex] metric tonne of water

[tex]V=1.1327[/tex]  metric tonne of water

Answer:

Coal is a traditionally used source of energy, there are main four types of ranks for coal. Here the rank of a coal means to a natural process called Coalification, which takes place during a plant is buried and changes to a harder, and denser material and become even more rich in carbon contents.

Anthracite is know to have the highest ranked coal, it contains highest percent of fixed carbon and lowest percent of volatile material.

Answer:

Their antibody is composed by subunits that have molecular weights of 50 kD and 25 kD, and each of these subunits has one Cys residue at least.

Explanation:

Their antibody is composed by subunits that are conected by an S-S bond that takes place in their Cys residue. When the antibody is treated with a reducing agent, these S-S bond are reduced to S-H, thus the subunits are no longer connected to each other.

The original antibody weights 150 kD, as seen in Lane 1. And the combination of these subunits are seen in Lane 2: this means there is not only one subunit of 50 kD and one of 25 kD. Rather, these subunits are repeated in the antibody, in a way such that their combined weight add ups to 150 kD (for instance 2 subunits of 50 kD and 2 subunits of 25 kD).

Final answer:

Based on SDS-PAGE analysis, investigators can conclude that the antibody under study is a multimeric protein made of polypeptide chains with molecular weights of 50 kD and 25 kD, held together by disulfide bonds that were reduced by mercaptoethanol.

Explanation:

Investigators utilized SDS-PAGE to analyze the purity of an antibody preparation. Upon electrophoresis, Lane 1, which contained untreated antibody sample, showed a single band at 150 kD. However, Lane 2, with antibody treated with mercaptoethanol, exhibited two distinct bands at molecular weights of 50 kD and 25 kD. The presence of these two bands in Lane 2, which was absent in Lane 1, indicates that the antibody molecule was originally composed of multiple polypeptide chains held together by disulfide bonds. Mercaptoethanol reduced these disulfide bonds, allowing the constituent polypeptide chains to be separated under electrophoretic conditions and revealing the true subunit composition of the antibody. Therefore, the investigators can conclude that the antibody is a multimeric protein, likely composed of two 50 kD chains and at least one 25 kD chain that were originally connected by disulfide bonds.

Explanation:

An ionic bond is generally formed by a metal and a non-metal.

For example, lithium is an alkali metal with atomic number 3 and its electronic distribution is 2, 1.

And, chlorine is a non-metal with atomic number 17 and its electronic distribution is 2, 8, 7.

So, in order to complete their octet lithium needs to lose an electron and chlorine needs to gain an electron.

Hence, both of then on chemically combining together results in the formation of an ionic compound that is, lithium chloride (LiCl).

An ionic compound is formed by LiCl because lithium has donated its valence electron to the chlorine atom.  

For example, [tex]O_{2}[/tex] is a covalent compound as electrons are being shared by each oxygen atom.