A sample of a compound is made up of 57.53 g C, 3.45 g H, and 39.01 g F. Determine the empirical formula of this compound.

Answer:

pH = 3.39

Explanation:

The equilibrium in water of ascorbic acid (With its conjugate base) is:

H₂C₆H₆O₆(aq) + H₂O(l) ⇄ HC₆H₆O₆⁻(aq) + H₃O⁺(aq)

Where the acidic dissociation constant is written as:

Ka = 7.9x10⁻⁵ = [HC₆H₆O₆⁻] [H₃O⁺] / [H₂C₆H₆O₆]

H₂O is not taken in the Ka expression because is a pure liquid.

As initial concentration of H₂C₆H₆O₆ is 2.5x10⁻³M, the equilibrium concentration of each species in the equilibrium is:

[H₂C₆H₆O₆] = 2.5x10⁻³M - X

[HC₆H₆O₆⁻] = X

[H₃O⁺] = X

Replacing in the Ka expression:

7.9x10⁻⁵ = [X] [X] / [2.5x10⁻³M - X]

1.975x10⁻⁷ - 7.9x10⁻⁵X = X²

0 = X² + 7.9x10⁻⁵X - 1.975x10⁻⁷

Solving for X:

X = -0.00048566→  False solution, there is no negative concentrations

X = 0.00040666 → Right solution

As [H₃O⁺] = X, [H₃O⁺] = 0.00040666

pH is defined as -log [H₃O⁺];

pH = -log 0.00040666,

Answer:

Alcl3 and Cl2

Explanation:

the product above will be formed

Answer:

silver (Ag) and aluminum chloride (AlCl₃)

Explanation:

The reaction between aluminum and silver chloride is a single replacement reaction. A single replacement reaction is when one element switches places with another.

Al + 3AgCl ➔︎ 3Ag + AlCl₃

In the reaction, the cations (positively charged ions) switch places. Aluminum (Al) switches places with Silver (Ag). So, the products of the reaction are silver and aluminum chloride.

Hope this helps.

Answer:

THE MASS OF 7.68 *10^24 MOLECULES OF PHOSPHORUS TRICHLORIDE IS 1746.25 g.

Explanation:

Molar mass of PCl3 = ( 31 + 35.5 *3) = 137.5 g/mol

At 7.68 * 10^24 molecules, how many number of mole is present?

6.03 * 10^23 molecules = 1 mole

7.68*10^24 molecules = x mole

x mole = 7.68 *10^24 molecules/ 6.03 *10^23

x mole = 1.27 *10 moles

x mole = 12.7 moles

Using mole = mass / molar mass

mass = mole * molar mass

mass = 12.7 moles * 137.5 g/mol

mass = 1746.25 g

Hence, the mass of 7.68 *10^24 molecules is 1746.25 g

Answer:

B. Reactant + Reactant -> Product + Product

Explanation:

Reactants are substances that- as the name suggests- reacts with other substances at the beginning of a reaction

Products are substances that are produced as a result of the reaction

Typically, when writing a chemical reaction, an arrow is used to show the direction the reaction is moving.  In this case, the arrows in options B and C suggest that the reaction only moves in one direction- forwards

And as mentioned above, reactants are the substances at the start of the reaction, they're what mixes together to form a new product.  

To keep things simple:

Products can't be at the beginning of a reaction since they weren't formed yet.

Similarly, reactants can't be part of the products since they already existed and didn't need to be made. In a lot cases, the reactants would be completely used up to make the products

As such, only one possible chemical reaction would follow that reasoning:

    Reactant + Reactant ->  Product + Product

Reactant + Reactant → Product + Product is the correctly written chemical reaction. Hence, option B is correct.

A chemical equation is a mathematical expression of the chemical reaction which represents the product formation from the reactants.

In an equation, the reactants are written on the left-hand side and the products are written on the right-hand side demonstrated by one-headed or two-headed arrows.

Hence, option B is correct.

Learn more about the chemical equation here:

https://brainly.com/question/12363199

#SPJ2

Answer:

3.01 × 10²³ molecules

Explanation:

Step 1: Given data

Moles of water (n): 0.500 mol

Step 2: Calculate the molecules of water present in 0.500 moles of water

In order to perform this calculation, we will use the Avogadro's number: in 1 mole of water there are 6.02 × 10²³ molecules of water.

0.500 mol × (6.02 × 10²³ molecules/1 mol) = 3.01 × 10²³ molecules

Answer:

A. Partial pressure of krypton, Kr is 346.97 mmHg

B. Partial pressure of nitrogen, N2 is 364.03 mmHg.

Explanation:

Step 1:

Data obtained from the question. This include the following:

Total pressure (Pt) = 711 mmHg

Mass of Kr = 11.7 g

Mass of N2 = 4.10 g

Partial pressure of Kr =..?

Partial pressure of N2 =...?

Step 2:

Determination of the number of mole of krypton, Kr and nitrogen, N2. This is illustrated below:

Molar mass of Kr = 84g/mol

Mass of Kr = 11.7g

Mole of Kr =?

Mole = mass /Molar mass

Mole of Kr = 11.7/84 = 0.139 mole

Molar mass of N2 = 2x14 = 28g/mol

Mass of N2 = 4.10g

Mole of N2 =?

Mole = mass /Molar mass

Mole of N2 = 4.1/28 = 0.146 mole

Step 3:

Determination of the mole fraction for each gas. This is illustrated below:

Mole of Kr = 0.139 mole

Mole of N2 = 0.146 mole

Total mole = 0.139 + 0.146 = 0.285 mole

Mole fraction of Kr = mol of Kr/total mol

Mole fraction of Kr = 0.139/0.285

Mole fraction of Kr = 0.488

Mole fraction of N2 = mol of N2/total mol

Mole fraction of N2 = 0.146/0.285

Mole fraction of N2 = 0.512

A. Determination of the partial pressure of krypton, Kr.

This is illustrated below:

Total pressure (Pt) = 711 mmHg

Mole fraction of Kr = 0.488

Partial pressure of Kr =..?

Partial pressure = mole fraction x total pressure

Partial pressure of Kr = 0.488 x 711

Partial pressure of Kr = 346.97 mmHg

B. Determination of the partial pressure of nitrogen, N2

This is illustrated below:

Total pressure (Pt) = 711 mmHg

Mole fraction of N2 = 0.512

Partial pressure of N2 =?

Partial pressure = mole fraction x total pressure

Partial pressure of N2 = 0.512 x 711

Partial pressure of N2 = 364.03 mmHg

Answer:

The new solution is 1.4% m/V

Explanation:

The concentration of the new solution, obtained by adding 22.5 mL of distilled water to 2.5 mL of 14 % m/V sugar solution, is 1.4% m/V.

We have 2.5 mL (V₁) of a concentrated solution and add it to 22.5 mL of distilled water. Assuming the volumes are additives, the volume of the new solution (V₂) is:

[tex]2.5 mL + 22.5 mL = 25.0 mL[/tex]

We want to prepare a dilute solution from a concentrated one, whose concentration is 14% m/V (C₁). We can calculate the concentration of the dilute solution (C₂) using the dilution rule.

[tex]C_1 \times V_1 = C_2 \times V_2\\C_2 = \frac{C_1 \times V_1}{V_2} = \frac{14\% m/V \times 2.5 mL}{25.0 mL} = 1.4 \% m/V[/tex]

The concentration of the new solution, obtained by adding 22.5 mL of distilled water to 2.5 mL of 14 % m/V sugar solution, is 1.4% m/V.

You can learn more about dilution here: https://brainly.com/question/13844449

Answer:

1. It dissolves much more ice faster than sodium chloride

2. Calcium chloride is more effective in melting ice at lower temperatures.

Explanation:

Salts are used to melt ice on roadways and sidewalks because they help to lower the freezing point of water.

Sodium chloride and calcium chloride are both salts used for this purpose but calcium chloride is usually preferred for the following two reasons:

1. It dissolves much more ice faster than sodium chloride: Calcium chloride dissolves much more ice faster than sodium chloride because when it dissociates, it produces three ions instead of the two produced when sodium chloride. Therefore, the heat of hydration of its ions is greater than that of sodium chloride.

2. Calcium chloride is more effective in melting ice at lower temperatures. It lowers the freezing point of water more than sodium chloride. Calcium chloride is able to lower the freezing point of water to about -52°C while sodium chloride only lowers it to about -6°C.

Answer:

Polarity in chemistry referred to physical properties of compounds related to solubility, melting and boiling properties.

Polarity of black pepper can be seen when black pepper is sprinkled on water. The balck pepper float on water and get displaced if touched.

It means black pepper is non-polar and have no difference in electronegativity between bonded atoms. Black pepper is so light in weight and non-polar, the surface tension of water keep it floating in the water.

Answer:

95.7 g CO to the nearest tenth.

Explanation:

2C + O2 ---> 2CO

Using relative atomic masses:

24 g C produces  2*12 + 2*16 g CO.

So 41 g produces  ( (2*12 + 2*16) * 41  ) / 24

= 95.7 g CO,

Answer:

1 mole of CaC₂ will produce 26g of C₂H₂ or 64.1g of CaC₂ will produce 26g of C₂H₂

Explanation:

Hello,

To solve this question, we'll require a balanced chemical equation of reaction between calcium carbide and water.

Equation of reaction

CaC₂ + 2H₂O → Ca(OH)₂ + C₂H₂

Molar mass of calcium carbide (CaC₂) = 64.1g/mol

Molar mass of water (H₂O) = 18g/mol

Molar mass of calcium hydroxide (Ca(OH)₂) = 74g/mol

Molar mass of ethyne (C₂H₂) = 26g/mol

From the equation of reaction, 1 mole of CaC₂ will produce 1 mole of C₂H₂

1 mole of CaC₂ = mass / molar mass

Mass = 1 × 64.1

Mass = 64.1g

1 mole of C₂H₂ = mass / molar mass

Mass = 1 × 26

Mass = 26g

Therefore, 1 mole of CaC₂ will produce 26g of C₂H₂

Note: this is a hypothetical calculation since we were not given the initial mass of CaC₂ that starts the reaction

Answer:

351.1g/mol

Explanation:

you can find the answer using The ideal gas equation

n= PV/RT

n=(1.21*1.9/0.082*301)mol

n=0.092 mol

molar mass=Mass/mole

m=32.3g/0.092mol

m=351.1g/mol

Answer:

3,4,1 and 6,5,2

Explanation:

In the electromagnetic spectrum the arrangement of the waves in increasing frequencies and decreasing wavelengths are as follows;

Radio waves

Microwaves

Infrared waves

Visible light rays

Ultraviolet rays

X-rays

Gamma rays

(a simple mnemonic is RMIVUXG)

Answer:

[tex]14\\8[/tex]O

Explanation:

The top number always represents the mass number.

The bottom number always represents the atomic number.

The element always goes after the numbers.

If charge is present, that comes after the element.

Answer:

4.26 %

Explanation:

There is some info missing. I think this is the original question.

Calculate the percent ionization of nitrous acid in a solution that is 0.249 M in nitrous acid. The acid dissociation constant of nitrous acid is  4.50  ×  10 ⁻⁴.

Step 1: Given data

Initial concentration of the acid (Ca): 0.249 M

Acid dissociation constant (Ka): 4.50  ×  10 ⁻⁴

Step 2: Write the ionization reaction for nitrous acid

HNO₂(aq) ⇒ H⁺(aq) + NO₂⁻(aq)

Step 3: Calculate the concentration of nitrite in the equilibrium ([A⁻])

We will use the following expression.

[tex][A^{-} ] = \sqrt{Ca \times Ka } = \sqrt{0.249 \times 4.50 \times 10^{-4} } = 0.0106 M[/tex]

Step 4: Calculate the percent ionization of nitrous acid

We will use the following expression.

[tex]\alpha = \frac{[A^{-} ]}{[HA]} \times 100\% = \frac{0.0106M}{0.249} \times 100\% = 4.26\%[/tex]

Answer:

B

Explanation:

All the elements in a period have valence electrons in the same shell. The number of valence electrons increases from left to right in the period. When the shell is full, a new row is started and the process repeats.

A new period starts when a new neutron cycle starts. Hence, option B is correct.

A period in the periodic table is a row of chemical elements. All elements in a row have the same number of electron shells.

All the elements in a period have valence electrons in the same shell.

The number of valence electrons increases from left to right in the period.

When the shell is full, a new row is started and the process repeats.

Hence, option B is correct.

Learn more about the period in the periodic table here:

https://brainly.com/question/3433177

#SPJ2

https://brainly.com/question/16061498?referrer=searchResults

Answer:

10.328 m

Explanation:

normal atmospheric pressure = 101325 Pa

density of water at 25 °C = 1.0 g/cm^3 = 1000 kg/m^3

pressure = pgh

where p = density

g = acceleration due to gravity = 9.81 m/s^2

h = height of column

imputing values, we have

101325 = 1000 x 9.81 x h

height of column h = 101325/9810 = 10.328 m

Answer:

[tex]m_{CO_2}=46.6gCO_2[/tex]

Explanation:

Hello,

In this case, considering the combustion of propane:

[tex]C_3H_8(g)+5O_2(g)\rightarrow 3CO_2(g)+4H_2O(g)\ \ \ \Delta _CH=-2220.0 kJ/mol[/tex]

We can compute the burnt moles of propane as shown below:

[tex]n=\frac{-784kJ}{-2220.0 kJ/mol} =0.353molC_3H_8[/tex]

Then, by noticing propane and carbon dioxide are in a 1:3 molar ratio, we can compute the grams carbon dioxide by using the shown below stoichiometric procedure:

[tex]m_{CO_2}=0.353molC_3H_8*\frac{3molCO_2}{1molC_3H_8} *\frac{44gCO_2}{1molCO_2} \\\\m_{CO_2}=46.6gCO_2[/tex]

Best regards.

Answer:

k= 1.5

[A] = 1 M

[B] = 3 M

m = 2

n = 1

Explanation:

rate = k[A]”[B]"

The rate of the reaction is 4.5 mol L⁻¹s⁻¹.

Rate of a reaction is defined as the change in concentration of any one of the reactants or products of the reaction, in unit time.

Here,

The concentration of A, [A] = 1 M

The concentration of B, [B] = 3 M

The partial order with respect to A, m = 2

The partial order with respect to B, n = 1

The rate constant of the reaction, k = 1.5

The rate of the reaction,

r = k[A]^m [B}^n

r = 1.5 x 1² x 3

r = 4.5 mol L⁻¹s⁻¹

Hence,

The rate of the reaction is 4.5 mol L⁻¹s⁻¹.

To learn more about rate of a reaction, click:

https://brainly.com/question/29049197

#SPJ2

Answer:

[tex]0.688M[/tex]

Explanation:

Hello,

In this case, it is widely acknowledged that strong bases usually correspond to those formed with metals in groups IA and IIA which have relatively high activity and reactivity, therefore, when they are dissolved in water the following dissociation reaction occurs (for calcium hydroxide):

[tex]Ca(OH)_2\rightarrow Ca^{2+}+2OH^-[/tex]

In such a way, for the same volume, we can compute the concentration of hydroxyl ions by simple stoichiometry (1:2 molar ratio):

[tex]0.344\frac{molCa(OH)_2}{L}*\frac{2molOH^-}{1molCa(OH)_2} \\\\0.688\frac{mol OH^-}{L}[/tex]

Or simply:

[tex]0.688M[/tex]

Regards.

Answer:

The correct answer is - 0.570 grams

Explanation:

The balanced chemical reaction is given by

Cu(NO3)2(aq)     + 2NaOH(aq)    -------->    Cu(OH)2(s)      + 2NaNO3(aq)

        1.0 mole            2.0 mole                 1.0 mole          2.0 mole

number of mol of Cu(OH)2,

n = Molarity * Volume

= [tex]35.0*0.167 = 5.845[/tex] millimoles

As clear in the equation, 1 mole of Cu(NO3)2 gives 1 mole of Cu(OH)2 , So, 5.845 millimoles of Cu(NO3)2 will produce 5.845 millimoles of Cu(OH)2

Mass of Cu(OH)2 = number of mol * molar mass

= [tex]97.5*5.845*10^-3[/tex]

= 0.570 grams

Thus, the correct answer is - 0.570 grams

Answer:

143pm is the radius of an Al atom

Explanation:

In a face centered cubic structure, FCC, there are 4 atoms per unit cell.

First, you need to obtain the mass of an unit cell using molar mass of Aluminium  and thus, obtain edge length and knowing Edge = √8R you can find the radius, R, of an Al atom.

Mass of an unit cell

As 1 mole of Al weighs 26.98g. 4 atoms of Al weigh:

4 atoms × (1mole / 6.022x10²³atoms) × (26.98g / mole) = 1.792x10⁻²²g

Edge length

As density of aluminium is 2.71g/cm³, the volume of an unit cell is:

1.792x10⁻²²g × (1cm³ / 2.71g) = 6.613x10⁻²³cm³

And the length of an edge of the cell is:

∛6.613x10⁻²³cm³ = 4.044x10⁻⁸cm = 4.044x10⁻¹⁰m

Radius:

As in FCC structure, Edge = √8 R, radius of an atom of Al is:

4.044x10⁻¹⁰m = √8 R

1.430x10⁻¹⁰m = R.

In pm:

1.430x10⁻¹⁰m ₓ (1x10¹²pm / 1m) =

The radius of the atom of Al in the FCC structure has been 143 pm.

The FCC lattice has been contributed with atoms at the edge of the cubic structure.

The FCC has consisted of 4 atoms in a lattice.

[tex]\rm 6.023\;\times\;10^2^3[/tex] atoms = 1 mole

4 atoms = [tex]\rm \dfrac{4}{6.023\;\times\;10^2^3}[/tex] moles

The mass of 1 mole Al has been 26.98 g/mol.

The mass of [tex]\rm \dfrac{4}{6.023\;\times\;10^2^3}[/tex] moles = [tex]\rm \dfrac{4}{6.023\;\times\;10^2^3}[/tex] moles × 26.98 g

The mass of 1 unit cell of Al has been = 1.792 [tex]\rm \bold{\times\;10^-^2^2}[/tex] g.

Density = [tex]\rm \dfrac{mass}{volume}[/tex]

Volume = Density × Mass

The volume of Al unit cell = 2.71 g/[tex]\rm cm^3[/tex] × 1.792 [tex]\rm \times\;10^-^2^2[/tex] g

The volume of Al cell = 6.613 [tex]\rm \times\;10^-^2^3[/tex] [tex]\rm cm^3[/tex]

Volume = [tex]\rm edge\;length^3[/tex]

6.613 [tex]\rm \times\;10^-^2^3[/tex] [tex]\rm cm^3[/tex] = [tex]\rm edge\;length^3[/tex]

Edge length = [tex]\rm \sqrt[3]{6.613\;\times\;10^-^2^3}[/tex] cm

Edge length = 4.044 [tex]\rm \times\;10^-^8[/tex] cm

Edge length = 4.044 [tex]\rm \bold{\times\;10^-^1^0}[/tex] m.

Edge length = [tex]\rm \sqrt{8\;\times\;radius}[/tex]

4.044 [tex]\rm \bold{\times\;10^-^1^0}[/tex] m = [tex]\rm \sqrt{8\;\times\;radius}[/tex]

Radius = 1.430 [tex]\rm \bold{\times\;10^-^1^0}[/tex] m.

1 m = [tex]\rm 10^1^2[/tex] pm

1.430 [tex]\rm \bold{\times\;10^-^1^0}[/tex] m = 143 pm.

The radius of the atom of Al in the FCC structure has been 143 pm.

For more information about the FCC structure, refer to the link:

https://brainly.com/question/14934549

Answer:

W= -11KJ

Explanation:

Given:

volume expands from 28 L to 51 L

pressure =4.9 atm.

We will need to Convert the pressure to Pascal SI

But 1 atm = 101,325 Pa.

Then,

Pressure= (4.9*101323)/1atm = 5*10^5 pa

Then we need to Convert the volumes to cubic meters

But we know that1 m³ = 1,000 L.

V1= 28L * 1m^3/1000L = 0.028m^3

V2=51L × 1m^3 /1000L =0.051m^3

The work done during the expansion of a gas can be calculated as

W= -P(V2-V1)

W= - 5*10^5(0.051m^3 - 0.028m^3)

W= -1.1× 10^4J

Then we can Convert the work to kiloJoule

But1 kJ = 1,000 J.

W= -1.1× 10^4J× 1kj/1000J

= -11KJ

The question is incomplete as some part is missing:

concentration in octanol Partition Ratio = concentration in water

a) What are the intermolecular forces of attraction between octanol molecules? Explain.

b) Which of the intermolecular forces of attraction identified in (a) account for most of the interactions between octanol molecules? Explain. Use the immiscibility in water and the data included in figures 1 and 2 as evidence to support your answer.

c) Would a compound with a partition coefficient less than one be more hydrophobic or more hydrophilic than one with a partition coefficient greater than 10? Explain.

d) Would nonane (figure 2) be more soluble in water or octanol? Explain.

e) Draw another structure for a compound with the same chemical formula as nonane (CH20) that has a lower boiling point. Explain.

f) Are any of the C atoms in the structure you drew for CH20 sp?hybridized? Explain.

Octanol Boiling point = 195°C Figure 2 Nonane (CH20) Boiling point = 151°C

Answer:

1. The forces between octanol molecules would be attractive. These forces include Vanderwaal forces, H-bonds due to the presence of highly polar O-H group.

2. H-bonding ahould account for most of the attractive forces. The O-H bond should behave like and dipole, oxygen of one molecule attracts the hydrogen of the neighbouring molecule forming D-H...A links throughout (D stands for donor of H-Bond and A for acceptor for H-Bond).

3. Partition coefficient less than 1 will be more hydrophilic, generally drugs with low partition coefficients are regarded as hydrophilic. As parition coefficient of 10 mean more of the solute is dispersed in octanol as compared to water.

4. Nonane is non polar, so it would not dissolve in water. It follows the rule like dissolves like. Polar substances dissolve in polar solvents. 1-octanol is able to bind with water through hydrogen bonds thus its soluble in water but nonane doesn't. Nonane will forms a different layer from water.

5) no all carbons in 2-methyloctane are single bonded. Thus sp3 hybrid. A sp2 hybridised carbon would have a double bond C=C.

Answer:

none of these statements is true

according to the question E) None of these statements is true.

The concentration of a chemical substance expresses the amount of a substance present in a mixture. There are many different ways to express concentration. Chemists use the term solute to describe the substance of interest and the term solvent to describe the material in which the solute is dissolved

Quantitative units of concentration include molarity, molality, mass percentage, parts per thousand, parts per million, and parts per billion.

Learn more about concentration here

https://brainly.com/question/24595796

#SPJ2

Answer:

#1: 0.00144 mmolHCl/mg Sample

#2: 0.00155 mmolHCl/mg Sample

#3: 0.00153 mmolHCl/mg Sample

Explanation:

A antiacid (weak base) will react with the HCl thus:

Antiacid + HCl → Water + Salt.

In the titration of antiacid, the strong acid (HCl)  is added in excess, and you're titrating with NaOH moles of HCl that doesn't react.

Moles that react are the difference between mmoles of HCl - mmoles NaOH added (mmoles are Molarity×mL added). Thus:

Trial 1: 0.391M×14.00mL - 0.0962M×34.26mL = 2.178 mmoles HCl

Trial 2: 0.391M×14.00mL - 0.0962M×33.48mL = 2.253 mmoles HCl

Trial 3: 0.391M×14.00mL - 0.0962M×33.84mL = 2.219 mmoles HCl

The mass of tablet in mg in the 3 experiments is 1515mg, 1452mg and 1443mg.

Thus, mmoles HCl /mg OF SAMPLE for each trial is:

#1: 2.178mmol / 1515mg

#2: 2.253mmol / 1452mg

#3: 2.219mmol / 1443mg

Answer:

The base is involved in the rate determining step of an E2 reaction mechanism

Explanation:

Let us get back to the basics. Looking at an E1 reaction, the rate determining step is unimolecular, that is;

Rate = k [Carbocation] since the rate determining step is the formation of a carbonation.

For an E2 reaction however, the reaction is bimolecular hence for the rate determining step we can write;

Rate = k[alkyl halide] [base]

The implication of this is that an excess of either the alkyl halide or base will facilitate an E2 reaction.

Hence, when excess base is used, E2 reaction is favoured since the base is involved in its rate determining step. In an E1 reaction, the base is not involved in the rate determining step hence an excess of the base has no effect on an E1 reaction.

Answer:

The total photons required = 5.19 × 10²⁸ photons

Explanation:

Given that:

the radiation wavelength λ= 12.5 cm = 0.125 m

Volume of the container = 0.250 L = 250 mL

The density of water = 1 g/mL

Density = mass /volume

Mass =  Volume ×  Density

Thus; the mass of the water =  250 mL ×  1 g/mL

the mass of the water = 250 g

the specific heat of water s = 4.18 J/g° C

the initial temperature [tex]T_1[/tex] = 20.0° C

the final temperature [tex]T_2[/tex] = 99° C

Change in temperature [tex]\Delta T[/tex] = (99-20)° C = 79 ° C

The heat q absorbed during the process = ms [tex]\Delta T[/tex]

The heat q absorbed during the process = 250 g × 4.18 J/g° C × 79° C

The heat q absorbed during the process = 82555 J

The energy of a photon can be represented by the equation :

= hc/λ

where;

h = planck's constant = [tex]6.626 \times 10^{-34} \ J.s[/tex]

c = velocity of light = [tex]3.0 \times 10^8 \ m/s[/tex]

=  [tex]\dfrac{6.626 \times 10^{-34} \times 3.0 \times 10^8}{0.125}[/tex]

= [tex]1.59024 \times 10^{-24}[/tex] J

The total photons required = Total heat energy/ Energy of a photon

The total photons required = [tex]\dfrac{82555 J}{1.59024 \times 10^{-24}J}[/tex]

The total photons required = 5.19 × 10²⁸ photons

Answer: 0.150 m [tex]Na_2SO_4(aq)[/tex] will have highest boiling point.

Explanation:

Formula used for Elevation in boiling point :

[tex]\Delta T_b=i\times k_b\times m[/tex]

where

[tex]\Delta T_b=T_b-T^o_b[/tex]= elevation in boiling point

[tex[k_b[/tex]  = boiling point constant  

m = molality

i = Van't Hoff factor

A) 0.100 m [tex]NiBr_2[/tex]

i = 3 as [tex]NiBr_2\rightarrrow Ni^{2+}+2Br^-[/tex]

concentration will be [tex]3\times 0.100=0.300[/tex]

B) 0.250 m [tex]CH_3OH[/tex]

i = 1 as [tex]CH_3OH[/tex] is a non electrolyte

concentration will be [tex]1\times 0.250=0.250[/tex]

C) 0.100 molal [tex]MgSO_4(aq)[/tex]

i = 2 as [tex]MgSO_4\rightarrrow Mg^{2+}+SO_4^{2-}[/tex]

concentration will be [tex]2\times 0.100=0.200[/tex]

D. 0.150 molal [tex]Na_2SO_4(aq)[/tex]

i = 3 as [tex]Na_2SO_4\rightarrrow 2Na^{+}+SO_4^{2-}[/tex]

concentration will be [tex]3\times 0.150=0.450[/tex]

E. 0.150 molal [tex]NH_4NO_3(aq)[/tex]

i = 2 as [tex]NH_4NO_3\rightarrrow NH_4^{+}+NO_3^{-}[/tex]

concentration will be [tex]2\times 0.150=0.300[/tex]

The solution having the highest concentration of ions will have the highest boiling point and thus 0.150 m [tex]Na_2SO_4(aq)[/tex] will have highest boiling point.

The aqueous solution that would have the highest temperature at boiling point would be:

D). 0.150 molal Na2SO4(aq)

The boiling point is described as the temperature at which the solution starts boiling or the vapor pressure becomes equivalent to the provided external/outer pressure.

To determine the elevation in boiling point, we will use:

Δ[tex]T_{b}[/tex] [tex]= i[/tex] × [tex]k_{b}[/tex] × [tex]m[/tex]

with

[tex]T_{b}[/tex] [tex]= T_{b} - T^{0}_{b}[/tex]

[tex]k_b[/tex] [tex]=[/tex] constant of boiling point

Using this formula,

0.150 molal Na2SO4(aq)

Given,

[tex]i = 3[/tex]

[tex]Na2So4[/tex] will have

[tex]2Na^{+}[/tex] [tex]+[/tex] [tex]SO^{2-}_{4}[/tex]

So,

Concentration [tex]= 3[/tex] × [tex]0.15[/tex][tex]0[/tex]

[tex]= 0.45[/tex][tex]0[/tex]

∵ 0.150 molal [tex]Na2SO4[/tex]Na2SO4(aq) has the maximum concentration.

Thus, option D is the correct answer.

Learn more about "Aqueous solution" here:

brainly.com/question/14097392

Answer:

7p

Explanation:

principal quantum number is 7

n=7( principle shell)

angular momentum quantum number gives sub shell

l = 1 means it is p orbital

so answer is 7p orbital