Which element would be a strong reducing agent?


F2

Ba

Na

Cl2

Answer:

A) dipole-dipole force

Explanation:

A dipole-dipole force is the type of intermolecular force that occurs between polar molecules.

The intermolecular force occurs between polar molecules is dipole-dipole bonding. The correct option is A)

Intermolecular forces are those forces that occur when two atom, molecules or ions come close together. There are different types of intermolecular force present between different molecules.

Thus, the correct option is A) dipole-dipole force

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Answer:

The nucleus of an atom consists of Protons and Neutrons.-A.

Answer :  The correct option is, Only Student B

Explanation :

Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.

In the Lewis-dot structure the valance electrons are shown by 'dot'.

The given molecule is, [tex]NH_3[/tex]

As we know that nitrogen has '5' valence electrons and hydrogen has '1' valence electron.

Therefore, the total number of valence electrons in [tex]NH_3[/tex] = 5 + 3(1) = 8

According to Lewis-dot structure, there are 6 number of bonding electrons and 2 number of non-bonding electrons.

The Lewis dot structure of student A is wrong because there is a coordinate bond present between the nitrogen and hydrogen is not covalent.

The correct Lewis-dot structure of [tex]NH_3[/tex] is shown by the student B.

Answer:

niether of them

Explanation:

the rest are bs

Answer:

Explanation:

The complete reaction equation is given as:

                         CO + 2H₂ ⇄ CH₃OH                       ΔH = -90.7kJmol⁻¹  

From the reaction equation, we know that:

According to Le Chatelier's principle, we know that "if any of the conditions of a system in equilibrium is changed, the system will adjust itself in order to annul the effect of the change".

For pressure changes:  

A change in pressure affects only equilibrium involving a gas or gases. An increase in pressure will shift the position of equilibrium to the side having smaller volume(or mole) and vice versa.

                          CO       +       2H₂ ⇄      CH₃OH

                          3 moles of gases        1 mole of gas

An increase in pressure will favor the production of more methanol since we have 3 moles of gas on the left hand side and just one mole of gas on the right hand side.

For temperature changes:

A rise in temperature shifts equilibrium to the direction that absorbs heat and vice versa. Since the reaction is exothermic in the forward reaction, a rise in temperature will favor the forward reaction. This would lead to the production of more methanol gas. A decrease in temperature will favor the backward reaction.

Animal obviously

It could be carnivore, herbivore or omnivore

Explanation:

perhaps is NO3

this question is somehow not correct

Answer:

NO₃⁻ is reduced; I₂ is oxidized

Explanation:

I think your equation is supposed to be

NO₃⁻ + I₂ ⟶ IO₃⁻ + NO₂

If you break the equation into two half-reactions, you get

NO₃⁻ + 2H⁺ + e⁻ ⟶ NO₂ + H₂O

I₂ + 3H₂O ⟶ IO₃⁻ + 6H⁺ + 5e⁻

We see that NO₃⁻ gains an electron, so it is reduced.

I₂ loses five electrons, so it is oxidized.

Answer:

Explanation:

You can deduce the ratio of PV to nRT from the ideal gas equation.

        ⇒ PV / nRT = 1.

Thus the ratio PV to nRT is constant and equal to 1, at all pressures, such as the statement B describes.

Hence, if P increases or decreases, the other variables, V, n, or T must change to keep the ration constant and equal to 1. R is the universal constant.

Answer:

The correct answer option is A. the ratio increases as the pressure increases.

Explanation:

We are to determine whether which of the given answer options explains how does a change in pressure affect the ration of PV to nRT.

We know that, for real gases:

[tex]PV = nRT[/tex]

where,

[tex] P [/tex] is the pressure of the gas ,

[tex] V [/tex] is the volume of gas ,

[tex] n [/tex] is the number of moles ,

[tex] R [/tex] is the gas constant; and

[tex] T [/tex]  is the temperature of the gas.

Gay-Lussac’s law states that for a constant volume, the pressure of that gas is directly proportional to the temperature on the Kelvin scale.

Therefore, the ratio increases as the pressure increases.

Answer:

The main difference between the two models was about the location of the electron in an atom.

Explanation:

Rutherford described that:

Bohr improved the Rutherford model:

Exact Answer:

In the Rutherford model, electrons can exist in any location outside the nucleus.

In the Bohr model, electrons can exist only in certain energy levels surrounding the atom.

Answer:

39698

Explanation:

Mass= 4.6kg

latent heat= 863

ML= 4.6*863= 39698

approximately = 397 In three significant figures

Answer : The specific latent heat of fusion of ice is, 187.608 J/g

Explanation :

Formula used :

[tex]Q=m\times L_f[/tex]

where,

Q = heat supply = 863 KJ = 863000 J

conversion used : (1 KJ = 1000 J)

m = mass of the substance = 4.6 Kg = 4600 g

conversion used : (1 Kg = 1000 g)

[tex]L_f[/tex] = specific latent heat of fusion = ?

Now put all the given values in the above formula, we get the specific latent heat of fusion of ice.

[tex]863000J=4600g\times L_f[/tex]

[tex]L_f=187.608J/g[/tex]

Therefore, the specific latent heat of fusion of ice is, 187.608 J/g

Answer:

frequency increases as wavelength decrease.

Explanation:

frequency = velocity/wavelength

Answer:

Frequncy increases, wavelength decreases

Explanation:

A wave can be defined as the repetitive pattern of a travelling energy. Waves can also be defined as a disturbance from equilibrium (or rest) of a medium which oscillates along a stable region. Examples of waves include: seismic waves, gravitational waves, shock waves, heat waves, sound waves etc

In a standing wave (ie at different points of the wave, amplitude is constant), its properties are:

Amplitude which is the the distance of the disturbance from equilibrium. It can also be defined as the distance between the highest point of the wave(peak or crest) to the lowest point (trough).

Wavelength(lambda) is the distance between one peak to the next peak or one trough to another trough parallel to the direction of propagation.

Frequency, f is the number of times a wave passes a particular point per unit time.

Wave velocity is the speed at which disturbance moves. It can given as an equation:

V = f*(lambda)

It can also be written as:

f = V/(lambda)

From the relationship above,

We can see that an increase in frequency of the wave would lead to a decrease in its wavelength and vice versa.

Answer:

there are 0.087 moles of ethanol in a 4.00 G sample of ethanol

Explanation:

Number of moles present in a substance is equal to the mass divided by molar mass.

Mathematically,      No. of moles = [tex]\frac{mass}{\text{molar mass}}[/tex]

As it is given that mass is 4.00 g and molar mass of [tex]CH_{3}CH_{2}OH[/tex] is 46.07 g/mol.

Hence, calculate the number of moles of [tex]CH_{3}CH_{2}OH[/tex] as follows.

                 No. of moles = [tex]\frac{mass}{\text{molar mass}}[/tex]

                                       = [tex]\frac{4.0 g}{46.07 g/mol}[/tex]

                                       = 0.086 mol

Thus, we can conclude that number of moles of [tex]CH_{3}CH_{2}OH[/tex] present in 4.00 g is 0.086 mol.

Answer:

In this theory, an acid is a substance that can release a proton (like in the Arrhenius theory) and a base is a substance that can accept a proton. A basic salt, such as Na+F-, generates OH- ions in water by taking protons from water itself (to make HF)

Answer:

Average atomic mass = 6.6575.

Explanation:

As fractions the abundance is 1/4 and 3/4.

The average atomic mass =  (5.03 + 3(7.20) / 4

= 6.6575.

Answer:

¹³₆C

Explanation:

The given nuclear reaction is:

          ¹⁰₅B + ₂⁴He → ᵃₙX + ₁¹H

In balancing nuclear reaction equation, the mass number which are the superscript and atomic number, the subscript on both sides of the equation must be the same.

For the mass number:

                  10 + 4 = a + 1

                  14 = a + 1

                    a = 13

For the atomic number:

             5 + 2 = n + 1

                7 = n + 1

                  n = 6

Note: n is the same as z from the equation

        therefore our atom is ¹³₆X which is an isotope of carbon, ¹³₆C

Answer:

2

Explanation:

The valency of an atom is the number of H atoms to which it can bond.

An atom of X can bond to two H atoms, so the valency of X is 2.

Answer:

[tex]\boxed{\text{17.76 \% by mass}}[/tex]

Explanation:

[tex]\text{The mass of one molecule of NH$_{3}$ is:}\\\text{14.01 u N + 3.024 u H = 17.034 u}\\\\\text{mass $\%$ H} =\dfrac{3.024}{17.034} \times 100 \%} =\textbf{17.76 \%}\\\\\text{Ammonia contains }\boxed{\textbf{17.76 \% H by mass}}[/tex]

Answer:

The reaction isn't yet at equilibrium. The overall reaction will continue to move in the direction of the products.

Assumption: this system is currently at [tex]\rm 900^{\circ}C[/tex].

Explanation:

One way to tell whether a system is at its equilibrium is to compare its reaction quotient [tex]Q[/tex] with the equilibrium constant [tex]K_c[/tex] of the reaction.

The equation for [tex]Q[/tex] is quite similar to that for [tex]K_c[/tex]. The difference between the two is that [tex]K_c[/tex] requires equilibrium concentrations, while [tex]Q[/tex] can be calculated even when the system is on its way to equilibrium.

For this reaction,

[tex]\displaystyle Q = \rm \frac{[CS_2]\cdot [H_2]^{4}}{[CH_4]\cdot [H_2S]^{2}}[/tex].

Given these concentrations,

[tex]\displaystyle Q = \rm \frac{[CS_2]\cdot [H_2]^{4}}{[CH_4]\cdot [H_2S]^{2}} =\frac{1.51\times (1.08)^{4}}{1.15\times (1.20)^{2}} \approx 1.72[/tex].

The question states that at [tex]\rm 900^{\circ}C[/tex], [tex]K_c = 3.59[/tex]. Assume that currently this system is also at [tex]\rm 900^{\circ}C[/tex]. (The two temperatures need to be the same since the value of [tex]K_c[/tex] depends on the temperature.)

It turns out that [tex]Q = K_c[/tex]. What does this mean?

In which direction will the system move? At this moment, [tex]Q < K_c[/tex]. As time proceeds, the value of [tex]Q[/tex] will increase so that it could become equal to [tex]K_c[/tex]. Recall that [tex]Q[/tex] is fraction.  

[tex]\displaystyle Q = \rm \frac{[CS_2]\cdot [H_2]^{4}}{[CH_4]\cdot [H_2S]^{2}}[/tex]

When the value of [tex]Q[/tex] increases, either its numerator becomes larger or its denominator becomes smaller, or both will happen at the same time. However,

As time proceeds,

In other words, the equilibrium will move towards the products.

The expression of 126.7 g in scientific notation results in 1.267 x 10^-1 kg.

To write 126.7 g in scientific notation, we need to convert it to kilograms. Since the base unit of mass in the SI system is the kilogram, we can express 126.7 g as 1.267 × 10-1 kg in scientific notation. Therefore, 126.7 g in scientific notation is 1.267 × 10-1 kg.

Answer:

Molecules of different gases with the same mass and temperature always have the same average kinetic energy - E.

Answer:

Molecules of different gases with the same mass and temperature always have the same average kinetic energy.

Answer:

[tex]\boxed{\text{6.02 $\math{\times 10^{21}}$ molecules}}[/tex]

Explanation:

A pressure of 1 atm and a temperature of 0 °C is the old definition of STP. Under these conditions, 1 mol of a gas occupies 22.4 L.

1. Calculate the moles of hydrogen.

[tex]n = \text{0.224 L} \times \dfrac{\text{1 mol}}{\text{22.4 L}} = \text{0.0100 mol}[/tex]

2. Calculate the number of molecules

[tex]\text{No. of molecules} = \text{0.0100 mol} \times \dfrac{\text{6.022 $\times 10^{23}$ molecules}}{\text{1 mol}}\\\\= \textbf{6.02 $\mathbf{\times 10^{21}}$ molecules}\\\\\text{The sample contains }\boxed{\textbf{6.02 $\mathbf{\times 10^{21}}$ molecules}}[/tex]

Answer:  6.02 × [tex]10^{21}[/tex] molecules of hydrogen are in the container. The Ideal Gas Law equation gives the relationship among the pressure, volume, temperature, and moles of gas.  Once the moles of gas is determined, we use Avogadro's number, 6.022 × [tex]10^{23}[/tex] to get he number of molecules.

Further Explanation:

The Ideal Gas Equation is:  

[tex]PV = nRT[/tex]  

where:  

P - pressure (in atm)  

V - volume (in L)  

n - amount of gas (in moles)  

R - universal gas constant [tex]0.08206 \frac{L-atm}{mol-K}[/tex]  

T - temperature (in K)  

In the problem, we are given the values:  

P = 1 atm  

V = 224 mL  = 0.224 L (3 significant figures)

n = ?

T = 0 degrees Celsius

We need to convert the temperature to Kelvin before we can use the Ideal Gas Equation. The formula to convert from degree Celsius to Kelvin is:  

[tex]Temperature \ in \ Kelvin = Temperature\ in \ Celsius \ + \ 273.15[/tex]  

Therefore, for this problem,  

[tex]Temperature\ in \ K = 0 +273.15\\Temperature\ in \ K = 273.15[/tex]  

Solving for n using the Ideal Gas Equation:  

[tex]n \ = \frac{PV}{RT}\\n \ = \frac{(1 \ atm) \ (0.224 \ L)}{(0.08206 \ \frac{L-atm}{mol-K})( 273.15 \ K)} \\ n \ = 9.99\ X \ 10^{-3} mol[/tex]

Now that we know the number of moles of hydrogen gas, we can determine how many molecules there are:

[tex]no.\ of \ molecules \ = moles \ of \ hydrogen \ (\frac{6.022 \ X \ 10^{23} molecules}{1 \ mole\ of \ hydrogen} )\\no.\ of \ molecules \ = 9.99 \ X \ 10^{-3} \ moles \ (\frac{6.022 \ X \ 10^{23} molecules}{1 \ mole\ of \ hydrogen} )\\ no. \ of \ molecules \ = 6.02 \ X 10^{21} \ molecules \ of \ hydrogen[/tex]

Learn More  

1. Learn more about Boyle's Law https://brainly.com/question/1437490  

2. Learn more about Charles' Law https://brainly.com/question/1421697  

3. Learn more about Gay-Lussac's Law https://brainly.com/question/6534668  

Keywords: Ideal Gas Law, Volume, Pressure  

Answer:

Here's what I get.

Explanation:

Your argument makes sense. For example, the density of C₅H₁₂ is about 0.63 g/mL, and it increases gradually to a limit of about 0.83 g/mL.  

With the lower alkyl halides, the halogen atom is the major contributor to the mass of the molecule. The density of chloromethane is 2.2 g/mL.

As you increase the number of C atoms, the Cl atom becomes a smaller part of the molecule. The alkyl halide becomes more like an alkane.

By the time you have reached four C atoms, the density has reached a limiting value of about 0.89 g/mL.

The combustion of carbon is a spontaneous process where carbon reacts with oxygen to form carbon dioxide. During this process, the enthalpy of the system decreases and the entropy increases.

The combustion of carbon, a chemical reaction involving carbon and oxygen, primarily results in the formation of carbon dioxide. This process is spontaneous under standard conditions, which means that it occurs naturally without needing any additional input. However, the statement that carbon is produced from oxygen and carbon dioxide is incorrect; rather, carbon and oxygen react to form carbon dioxide in a combustion reaction.

From the thermodynamic perspective, the enthalpy of the system decreases as heat is released during the combustion, so it's not true that enthalpy remains constant. This is an exothermic reaction, which involved a negative change in enthalpy. The entropy, or the degree of randomness or disorder, increases due to the production of gas molecules from a single carbon atom and oxygen molecule, contrary to the claim that the entropy decreases.

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At  [tex]\fbox{\begin \\363 K \end{minispace}}[/tex]  temperature, a sample of neon gas will occupy [tex]50.00 \text{ m}^{3}[/tex] volume.

Further Explanation:

The given problem is based on the concept of Charles’ law. Charles’ law states that “at constant pressure and fixed mass the volume occupied an ideal gas is directly proportional to the Kelvin temperature.”

Mathematically the law can be expressed as,

[tex]\fbox{ \begin \\ V \propto T \end{minispace}}[/tex]

Or,

[tex]\frac{V}{T}=k[/tex]

Here, V is the volume of the gas, T is Kelvin temperature, and k is proportionality constant.

Given information:

The initial volume of neon gas is [tex]40.81 \text{ m}^{3}[/tex] .

The final volume of neon gas is  [tex]50.00 \text{ m}^{3}[/tex].

The initial temperature value is [tex]23.5 \text{ } ^{\circ} \text{C}[/tex] .

To calculate:

The final temperature

Given Condition:

Solution:

Step 1: Modify the mathematical expression for Charles’ law for two different temperature and volume values as follows:

[tex]\frac{V_{1}}{T_{1}}=\frac{V_{2}}{T_{2}}[/tex]

Here,

Step 2: Rearrange equation (2) for .

[tex]\fbox {\begin \\T_{2}=\frac{(V_{2}) \times (T_{1})}{V_{1}}\\\end{minispace}}[/tex]                                                                  …… (2)

Step 3: Convert the given temperature  from degree Celsius to Kelvin.

The conversion factor to convert degree Celsius to Kelvin is,

[tex]T(\text{K}) = T(^{\circ}\text{C}) + 273.15[/tex]                                      …… (3)

Substitute [tex]23.5\text{ }^{\circ} \text{C}[/tex] for [tex]T(^{\circ}\text{C})[/tex]  in equation (3) to convert temperature from degree Celsius to Kelvin.

[tex]T(\text{K}) = 23.5 \text{ } ^{\circ} \text{C} + 273.15\\T(\text{K})= 296.65 \text{ K}[/tex]

Step 4: Substitute [tex]40.81 \text{ m}^{3}[/tex]  for [tex]V_{1}[/tex] ,  [tex]50.00 \text{ m}^{3}[/tex] for [tex]V_{2}[/tex]  and  [tex]296.65 \text{ K}[/tex] for [tex]T_{1}[/tex]  in equation (2) and calculate the value of [tex]T_{2}[/tex] .

[tex]T_{2}=\frac{(50.00 \text{ m}^{3}) \times (296.65 \text{ K})}{40.81 \text{ m}^{3}}\\T_{2}=363.45 \text{ K}\\T_{2} \approx 363 \text{ K}[/tex]

Important note:

Learn More:

1. Gas laws https://brainly.com/question/1403211

2. Application of Charles’ law https://brainly.com/question/7434588

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: States of matter

Keywords: neon, volume, occupies, temperature, Kelvin, degree Celsius, Charle’s law, constant pressure, fixed mass, 40.81 m^3 , 50.00 m^3 , 23.5 degree C , celsius , 363 K , sates of matter, initial volume, final volume, initial temperature, final temperature, V1 , V2 , T1 , T2 .

At 363.27 degrees temperature, in Kelvins, the gas occupies 50.00 cubic meters.

Charles' law (also known as the law of volumes) is an experimental gas law that describes how gases tend to expand when heated.

To calculate the final temperature of the system, we use the equation given by Charles' Law. This law states that the volume of the gas is directly proportional to the temperature of the gas at constant pressure.

Mathematically,

[tex]\frac{V_1}{T_1} = \frac{V_2}{T_2}[/tex]

where,

[tex]V_1[/tex] and [tex]T_1[/tex] are the initial volume and temperature of the gas.

[tex]V_1[/tex]and [tex]T_2[/tex] are the final volume and temperature of the gas.

Apply Charles' Law which states that the volume of a gas at constant pressure is directly proportional to the Kelvin temperature.

23.5 C = 273 + 23.5 = 296.5 degrees K.

40.81 / 296.5 = 50 ÷ x   where x is the required temperature.

x = 363.27 degrees.

Hence, At 363.27 degrees temperature, in Kelvins, the gas occupies 50.00 cubic meters.

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Answer:

0.7M

Explanation:

Volume of NaOH = 35mL = 0.035L

Concentration of NaOH = 0.5M

Volume of HCl = 25mL = 0.025L

Concentration of HCl = ?

Solution;

The balanced equation of the reaction is shown below:

              NaOH + HCl  → NaCl + H₂O

To solve this problem, we solve from the known to the unknow. The known here is the parameters of NaOH. From here, we can find the number of moles;

Number of moles of NaOH = concentration x volume= 0.035 x 0.5

                                             = 0.0175mole

From the balanced reaction equation, we can state that:

       1 mole of NaOH reacted with 1 mole of HCl

         0.0175mole of NaOH will reacted with 0.0175mole of HCl

Now that we know the number of moles of the acid used, we can calculate the concentration of the acid used using the expression below:

  Concentration of acid = [tex]\frac{number of moles of acid}{volume of acid}[/tex]

 Concentration of acid= [tex]\frac{0.0175}{0.025}[/tex] = 0.7M

Answer:

1: it can produce crops that are resistant to pest

2: it can result in animals that can produce more food

Explanation:

i had the same question

The exothermic reaction among the choices is B. iron rusting. An exothermic reaction is a reaction that releases heat. Rust is formed from the reaction of iron with oxygen. This reaction releases heat, hence, an exothermic reaction.

Further Explanation:

A. melting ice is an endothermic process. An endothermic process requires the absorption of energy from the surroundings. Heat is needed to change ice to liquid water. That is why, when ice is removed from the freezer and left on a warmer place it melts. The heat from the surroundings is absorbed by the ice causing it to change to liquid phase.

B. iron rusting is exothermic. Heat is released when oxygen and iron react to form rust.

C. dissolving sugar in water is an endothermic process. Heat is needed to break up the intermolecular forces of attraction holding the sugar molecules together. Also, adding heat makes the process of dissolution faster

D. dissolving ammonium nitrate in water is an endothermic process. A characteristic of endothermic reactions is that it turns the container of a substance colder. As the substance absorbs heat from the surroundings, the temperature of the surroundings, including the container, decreases. In exothermic reactions, heat is released to the surroundings making the container feel hotter during and after the reaction.

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Keywords: exothermic reaction, endothermic reaction

Answer:

AlCl₃.

Explanation:

Adding solute to water causes depression of the boiling point.

The depression in freezing point (ΔTf) can be calculated using the relation:

ΔTf = i.Kf.m,

where, ΔTf is the depression in freezing point.

i is the van 't Hoff factor.

van 't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass. For most non-electrolytes dissolved in water, the van 't Hoff factor is essentially 1.

Kf is the molal depression constant of water.

m is the molality of the solution (m = 1.0 m, for all solutions).

(1) NaCl:

i for NaCl = no. of particles produced when the substance is dissolved/no. of original particle = 2/1 = 2.

∴ ΔTb for (NaCl) = i.Kb.m = (2)(Kf)(1.0 m) = 2(Kf).

(2) MgCl₂:

i for MgCl₂ = no. of particles produced when the substance is dissolved/no. of original particle = 3/1 = 3.

∴ ΔTb for (MgCl₂) = i.Kb.m = (3)(Kf)(1.0 m) = 3(Kf).

(3) NaCl:

i for KBr = no. of particles produced when the substance is dissolved/no. of original particle = 2/1 = 2.

∴ ΔTb for (KBr) = i.Kb.m = (2)(Kf)(1.0 m) = 2(Kf).

(4) AlCl₃:

i for AlCl₃ = no. of particles produced when the substance is dissolved/no. of original particle = 4/1 = 4.

∴ ΔTb for (CoCl₃) = i.Kb.m = (4)(Kf)(1.0 m) = 4(Kf).

Answer: AlCl₃. :) de nada

Answer:

Cell membranes

Explanation:

Cell membranes is a feature that is common to prokaryotic and eukaryotic cells.

Answer:cell membranes

Explanation:

Answer:

cell walls

Explanation:

because the rigid structure that surrounds the cell membrane and provides support to the cells

Answer:

A. Cell wall

B. Cell membrane

Hope this Helps!

Answer:

[tex]\boxed{\text{6.022 $\times 10^{23}$ kg; 2.5 $\times 10^{-4}$\ mol}}[/tex]

Explanation:

1. Mass of 1 mol of bricks

[tex]m = 6.022 \times 10^{23}\text{ bricks} \times \dfrac{\text{4.0 kg}}{\text{ 1 brick}} = 2.4 \times 10^{24}\text{ kg}\\\\\text{The mass of 1 mol of bricks is }\boxed{\textbf{2.4 $\times\mathbf{10^{24}}$ kg}}[/tex]

2. Number of moles

(a) Convert grams to kilograms

[tex]6.0 \times 10^{24}\text{ g} = 6.0 \times 10^{21}\text{ kg}[/tex]

(b) Convert kilograms to moles

[tex]n = 6.0 \times 10^{21}\text{ kg} \times \dfrac{\text{1 mol bricks }}{2.4 \times 10^{24}\text{ kg}} = \text{0.0025 mol bricks}\\\\\text{The mass of the Earth equals the mass of }\boxed{\textbf{0.0025 mol of bricks}}[/tex]

Answer: The mass of 1 mole of brick is [tex]24.088\times 10^{26}g[/tex] and the moles of brick having same mass as earth is 2.49 moles.

Explanation:

We are given:

Mass of a brick = 4.00 kg = 4000 g  (Conversion factor:  1 kg = 1000 g)

According to mole concept:

[tex]6.022\time 10^{23}[/tex] number of atoms are contained in 1 mole of an atom.

As, mass of 1 brick is 4000 g

So, mass of [tex]6.022\times 10^{23}[/tex] number of bricks will have = [tex]\frac{4000}{1}\times 6.022\times 10^{23}=24.088\times 10^{26}g[/tex]

Now, calculating the moles of brick having the mass equal to the mass of Earth.

Mass of Earth = [tex]6\times 10^{27}g[/tex]

To calculate the moles of bricks, we apply unitary method, we get:

[tex]24.088\times 10^{26}g[/tex] of mass is occupied by 1 mole of brick

So, [tex]6.0\times 10^{27}g[/tex] of mass will be occupied by [tex]\frac{1}{24.088\times 10^{26}}\times 6.0\times 10^{27}=2.49moles[/tex]

Hence, the mass of 1 mole of brick is [tex]24.088\times 10^{26}g[/tex] and the moles of brick having same mass as earth is 2.49 moles.