3. Which of the rocks from the table would be classified as metamorphic rocks?


A.
Gneiss and slate, only


B.
Granite, only


C.
Limestone and basalt, only


D.
Coal, only

Carbon dioxide is considered to be a greenhouse gas because it absorbs and emits infrared radiation.

Greenhouse gases like carbon dioxide trap heat in the atmosphere, leading to the warming of the Earth's surface and atmosphere.Carbon dioxide is a greenhouse gas, meaning that it can absorb and emit infrared radiation. Carbon dioxide and other greenhouse gases in the atmosphere act as a type of insulation, trapping heat and keeping the Earth's surface and atmosphere warm.A greenhouse gas is a gas that can absorb and emit infrared radiation. The greenhouse effect occurs when certain gases, such as carbon dioxide and water vapor, trap heat in the Earth's atmosphere. As more greenhouse gases are released into the atmosphere, the Earth's temperature increases, leading to climate change.

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Answer:

Alright, We all know fruits contains enzyme, so there is a reaction name enzymic browning! Actually what happens when we cut the apple and keep it open the organic enzyme molecules starts reacting with oxygen of surroundings and oxidises it!

To determine the weight of an empty cylinder, we will consider the given information below:Half full of water cylinder weighs 11.6 kgFilled with a third of water, the cylinder weighs 10 kg.The glass cylinder is unmarked.Let's assume that the empty cylinder weighs x kg.

Since water was used to fill the cylinder, we know that the density of water is 1 g/cm³ or 1 kg/L.To find the volume of water needed to fill half of the cylinder, we will subtract the weight of the empty cylinder from the weight of the half-filled cylinder. Thus, volume of water filled in the cylinder is 11.6 kg - x kg. Since the cylinder is half-full, we will multiply the volume of water by 2, then divide by the total volume of the cylinder. Thus, we have:[tex]\frac{2\cdot(11.6kg-x kg)}{Volume}[/tex]Similarly, we can find the volume of water needed to fill a third of the cylinder using the formula above. Thus, we have:[tex]\frac{3\cdot(10kg-x kg)}{Volume}[/tex]Since the density of water is 1 kg/L, we know that the volume of water is equal to the weight of the water. Equating the two expressions, we have:2(11.6 - x) = 3(10 - x)Solving for x, we have x = 2.8 kg. Therefore, the empty cylinder weighs 2.8 kg.Answer: The empty cylinder weighs 2.8 kg.

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Answer:

150,000 Joules

Explanation:

KE= 1/2 *mv^2

1/2 * 120 *50^2

60*2500

150,000 Joules

Hope this helps :)

The correct statement which are true about a galvanic cell that has an E value of 1.00V are The reaction is spontaneous and It has a negative ΔG°. Hence, the correct option is e. The species produced by a beta emission by magnesium-27 is no specific isotope or element. Hence, the correct option is e.

A galvanic cell with an E value of 1.00V indicates that the cell reaction is spontaneous. The E value represents the cell potential, and a positive E value indicates that the reaction will proceed spontaneously in the forward direction.

At equilibrium, the cell potential would be zero (E = 0), but the given cell has an E value of 1.00V. Therefore, statement II is incorrect. The equilibrium constant (K) is not necessarily equal to 1 in a galvanic cell.

The ΔG° (standard Gibbs free energy change) is related to the E value of the cell by the equation: ΔG° = -nFΔE°, where n is the number of moles of electrons transferred and F is the Faraday constant. Since the E value is positive (1.00V), the ΔG° will be negative, indicating that the cell reaction is thermodynamically favorable. Therefore, statement III is true.

Therefore, the correct answer is e. I and III.

The beta emission by magnesium-27 (27Mg) would result in the production of an electron (β- particle). Therefore, the correct answer is e. None. No specific isotope or element is produced by the beta emission of magnesium-27.

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Answer:

6.6M

Explanation:

C=concentration

V=Volume

C1V1=C2V2

rearrange formula to find C2

(C1V1)/V2= C2

(12M x 550mL)/1000mL= C2

6600M*mL*/1000*mL* =C2 (cancel units)

6.6M=C2

Answer:

hydroxyl (OH)

Explanation:

hydroxyl (OH)

The correct option is a. 618.1

Given data: Substances : NH3 (g) -46.19 192.5 HCl (g) -92.30 186.69 NH4Cl (s) -314.4 94.6

We are to determine the temperature (in °C) above which the reaction is nonspontaneous.

We can determine this by calculating ΔG for the reaction.

The equation to calculate ΔG is as follows:ΔG° = ΣG°(Products) - ΣG°(Reactants) ,    

From the given data, we can write:ΔG° = G°(NH4Cl) - [G°(NH3) + G°(HCl)]

Substituting the values:ΔG° = (-314.4) - [(-46.19) + (-92.30)]ΔG° = (-314.4) + 138.49ΔG° = -175.91 kJ/mol

Now we can use the equation:ΔG = ΔH - TΔS

At non-spontaneous reaction, ΔG = 0.

We can re-arrange the equation and solve for T to get the temperature at which the reaction is non-spontaneous.

T = ΔH / ΔS = (-175.91 kJ/mol) / (-192.5 J/mol-K) = 911.9 K = 638.7 °C

Therefore, the temperature above which the reaction is nonspontaneous is 638.7 °C (approx.)

Hence, the correct option is a. 618.1.

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Answer:

NaBr

Explanation:

Answer:

um...id.k how to do chemistry...help please?

Explanation:

NaBr

The moles of propane consumed in the reaction is approximately 4.00 moles. Option B is correct.

The balanced equation for the reaction is;

C₃H₈(g) + 5 O₂(g) → 3 CO₂(g) + 4 H₂O(g)

According to the stoichiometry of the reaction, for every 1 mole of C₃H₈, 5 moles of O₂ are required for complete combustion.

Given that you start with 4.00 moles of C₃H₈ and 4.00 moles of O₂, we need to determine the limiting reactant to determine the moles of propane consumed.

For C₃H₈:

moles of C₃H₈ = 4.00 moles (given)

For O₂;

moles of O₂ = 4.00 moles (given)

To determine the limiting reactant, we need to compare the mole ratios of the reactants to the stoichiometry of the balanced equation.

For C₃H₈;

moles of C₃H₈ used = 4.00 moles

For O₂;

moles of O₂ required = 5 moles of O₂ per 1 mole of C₃H₈

moles of O₂ required = 5 × 4.00 moles = 20.00 moles

Comparing the moles of C₃H₈ used (4.00 moles) and the moles of O₂ required (20.00 moles), we can see that the moles of C₃H₈ used are less than the moles of O₂ required. This means that C₃H₈ is the limiting reactant.

Therefore, the moles of propane is 4.00 moles.

Hence, B. is the correct option.

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--The given question is incomplete, the complete question is

"Consider the reaction below. If you start with 4.00 moles of C₃H₈ (propane) and 4.00 moles of O₂, how many moles of propane would be consumed? C₃Hg(g) + 5 O₂(g) + 3 CO₂(g) + 4H₂O(g) A) 3.20 B) 4.00 C) 20.0 D) 2.00 E) 0.800."--

Dispersion forces (London dispersion forces), dipole-dipole, and hydrogen bonding will occur between two molecules of CH3NH2.

Molecule of CF4, the molecular geometry is tetrahedral. The C-F bonds are polar and tetrahedral. The molecule is nonpolar.Intermolecular forces are forces that hold molecules together. There are three types of intermolecular forces: dispersion forces, dipole-dipole forces, and hydrogen bonding. The forces are affected by the type of molecule and the presence of polar groups. The intermolecular forces between two molecules of CH3NH2 are dispersion forces and hydrogen bonding. The correct options are:A) Dispersion forces (London dispersion forces)B) Dipole-dipoleC) Hydrogen bondingD) Ion-dipole forcesExplanation: CH3NH2 has a dipole moment, so it can participate in dipole-dipole interaction. Also, it has H atoms attached to nitrogen which makes it capable of forming hydrogen bonding. Thus, dispersion forces (London dispersion forces), dipole-dipole, and hydrogen bonding will occur between two molecules of CH3NH2.

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Answer:

Length of RT = 9.22 cm to the nearest hundredth

Explanation:

Considering the image up in the attachment, ΔRST is a right-angled triangle.

The length of two sides of ΔRST is given as 11cm and 6 cm. The length of the third side which is RT can be obtained using Pythagoras ' rule which says that the sum of the squares of two sides of a right-angled triangle is equal to the square of the hypotenuse.

This rule is given as: c² = b² + a² where c is the hypotenuse and a and b are the other two sides of the right-angled triangle.

In ΔRST, the length of the hypotenuse = 11 cm, the length of one of the two sides = 6cm, length of RT = x

Solving for x: (11 cm)² =  (x cm)² + (6 cm)²

(x cm)² = 121 cm² - 36 cm²

(x cm)² = 85 cm²

x cm = √85

x = 9.22 cm to the nearest hundredth

Therefore, length of RT = 9.22 cm to the nearest hundredth

Answer: The male reproductive system contains the TESTES; which PRODUCE SPERM. The correct option is D

Explanation:

There are different organ systems in the human body which functions together to bring about the normal healthy status of an individual. To list but a few, these systems include:

--> skeletal and muscular system

--> Endocrine System,

--> Nervous System, and

--> REPRODUCTIVE SYSTEM

The reproductive system is made up of the male and the female reproductive system which are very different as it's consists of different organs with different functions.

The male reproductive system consists of:

--> scrotum

--> Testes

--> prostate gland

--> seminal vesicles

--> penis.

The SPERM (spermatozoa) are produced in the seminiferous tubules of the TESTES and mature as they pass through the long and convoluted epididymis, where they are stored. Therefore option D is the correct answer.

A chemical substance that is extremely stable and takes years to break down into a less toxic form would be considered to be persistent. Persistence refers to the ability of a substance to resist degradation or breakdown over time.

Persistent chemicals have a long environmental or biological half-life, meaning it takes a significant amount of time for them to degrade or transform into less harmful substances.

Persistence can have negative implications because these substances can persist in the environment, accumulate in living organisms, and potentially cause adverse effects.

Examples of persistent substances include certain synthetic chemicals like some pesticides, certain industrial pollutants, and some persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) and certain chlorinated pesticides.

The persistence of a chemical is an important factor to consider when assessing its potential environmental and health impacts.

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A coffee cup temperature  with a heat capacity of 6. 70 J/∘ C was used to measure the change in enthalpy of a precipitation reaction.The value of ΔHrxn was found to be 61.9 kJ/mol.

Calculate the enthalpy of reaction, ΔHrxn, per mole of precipitate formed (AgSCN). Assume the specific heat of the product solution is 4. 11 J / (g⋅∘C) and that the density of both the reactant solutions is 1. 00 g/mL.1. Calculation of Moles of precipitate formed from AgNO3:To find the value of ΔHrxn, we used the formula ΔHrxn = Qsolution/n, where Qsolution is the heat change produced by the solution process and n is the number of moles of AgSCN formed.

To find the value of n, we first calculated the number of moles of AgNO3 and KSCN used in the reaction using the formula n = M × V.To find the heat change produced by the solution process, we used the formula

Q = m × c × ∆T,

where Q is the heat change, m is the mass of the product solution, c is the specific heat capacity of the product solution, and ∆T is the change in temperature of the solution.The value of ΔHrxn was found to be 61.9 kJ/mol.

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Answer:

Yes, the combustion of hydrogen is spontaneous from the given conditions.

Explanation:

Let look at the reaction:

[tex]2H_2_{(g)} + O_2_{(g)} \to 2H_2O_{(g)}[/tex]

[tex]K_p = \dfrac{[P(H_2O)]^2}{[P(H_2)^2\times P(O_2)]} ----- (1)[/tex]

The total pressure of the tank = 1 atm

[tex]\mathtt{Pressure \ of \ the \ gas = moles \ fraction \of \ gas \times total \ pressure}[/tex]

Thus, pressure of [tex]O_2[/tex] gas = [tex]\dfrac{9.38 \times 10^{-3} }{(9.38 \times 10^{-3} + 2.46 \times 10^{-8} + 1.79 \times 10^{-4}} \times 1 atm[/tex]

[tex]P(O_2) = 0.9813 atm[/tex]

Pressure of [tex]H_2O[/tex] gas =[tex]\dfrac{1.78 \times 10^{-4}}{9.38 \times 10^{-3} + 2.46 \times 1)^{-8} + 1.78 \times 10^{-4}} \times 1 \ atm[/tex]

Pressure of H_2 gas = [tex]2.573 \times 10^{-6} \ atm[/tex]

From equation (1);

[tex]K_p = \dfrac{(0.0187)^2}{(2.573 \times 10^{-6})^2 \times (0.913) } \\ \\ K_p = 5.383 \times 10^7[/tex]

So, applying the equation:

[tex]\Delta G^0 = -RT In K_p \\ \\ = -8.314 \times (300)K \times IN(5.383 \times 10^7) \\ \\ = -45880.109 J \\ \\ = -45.800 \ kJ\\ \\[/tex]

Thus;

[tex]\Delta G^0 < 0[/tex]

Thus, Yes the combustion of hydrogen is spontaneous from the above conditions. From thermodynamics, we realize that assuming ∆G is negative, the reaction is spontaneous. Again we understand that ∆G=∆H-T∆S. However, for combustion, water will definitely be formed.

Finally, we can conclude that;

∆H is negative;

∆S is positive; &

∆G is also negative.

Thus, from above, we conclude combustion of hydrogen is spontaneous.

The combustion of hydrogen gas with the oxygen gas for the formation of the water vapor is a spontaneous reaction.

To know about the condition that the given reaction is spontaneous or not we will use the below equation and must get the negative value:

ΔG° = -RTlnKp, where

R = universal gas constant

T = temperature

Kp = partial pressure constant

Firstly we have to calculate the value of Kp.

Given chemical reaction is:

2H₂(g) + O₂(g) → 2H₂O(g)

Value of Kp for the given reaction is:

Kp = [p(H₂O)]² / [p(H₂)]².[p(O₂)]

Partial pressure will be calculated as:

p = mole fraction × total pressure

Given that total pressure of gas = 1atm

p(H₂O) = (1.79×10⁻⁴ / 1.79×10⁻⁴+2.46×10⁻⁸+9.38×10⁻³) × 1 = 0.0187

p(H₂) = (2.46×10⁻⁸ / 1.79×10⁻⁴+2.46×10⁻⁸+9.38×10⁻³) × 1 = 2.573 × 10⁻⁶

p(O₂) = (9.38×10⁻³ / 1.79×10⁻⁴+2.46×10⁻⁸+9.38×10⁻³) × 1 = 0.913

Putting all these values on the equation of Kp, we get

Kp = (0.0187)² / (2.573 × 10⁻⁶)²(0.913) = 5.383 × 10⁷

Now putting values in the first equation we get,

ΔG° = -(8.314)(300)ln(5.383 × 10⁷)

ΔG° = -45,800 kJ

Hence, given reaction is spontaneous.

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Answer:

This regulatory mechanism is in conjunction with the endocrine system, particularly in the posterior pituitary gland. This is related in the secretion of vasopressin or antidiuretic hormone (ADH). In the event of dehydration or extreme thirst, the body will conserve as much fluid as possible and the posterior pituitary will secrete more ADH that will signal the kidney to reabsorb more water in the collecting tubules.

The final temperature of the aluminum engine part is approximately 284.19 degrees Celsius.

To determine the final temperature of the aluminum engine part, we can use the equation:

q = m × c × ΔT

Where:

q is the heat absorbed (in J)

m is the mass of the aluminum part (in g)

c is the specific heat capacity of aluminum (in J/g·K)

ΔT is the change in temperature (in K)

First, let's convert the mass of the aluminum part from grams to kilograms:

295 g = 0.295 kg

We are given the heat absorbed as 75.0 kJ, which is equal to 75,000 J.

Now, let's rearrange the equation to solve for ΔT:

ΔT = q / (m × c)

Substituting the values:

ΔT = 75,000 J / (0.295 kg × 0.900 J/g·K)

Calculating ΔT:

ΔT = 271.19 K

To find the final temperature, we need to add the change in temperature to the initial temperature:

Final temperature = Initial temperature + ΔT

Final temperature = 13.00°C + 271.19 K

Converting back to Celsius:

Final temperature = 284.19°C

Therefore, the aluminum engine part's ultimate temperature is approximately 284.19 degrees Celsius.

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Answer:

2.41*10² m equals 2.41*10⁴ cm

Explanation:

The rule of three or is a way of solving problems of proportionality between three known values and an unknown value, establishing a relationship of proportionality between all of them. That is, what is intended with it is to find the fourth term of a proportion knowing the other three. Remember that proportionality is a constant relationship or ratio between different magnitudes.

If the relationship between the magnitudes is direct, that is, when one magnitude increases, so does the other (or when one magnitude decreases, so does the other) , the direct rule of three must be applied. To solve a direct rule of three, the following formula must be followed:

a ⇒ b

c ⇒ x

So: [tex]x=\frac{c*b}{a}[/tex]

In this case the rule of three can be applied as follows: if 1 m equals 100 cm, 2.41*10² m equals how many cm?

[tex]cm=\frac{2.41*10^{2} m*100 cm}{1 m}[/tex]

cm= 24100 = 2.41*10⁴

2.41*10² m equals 2.41*10⁴ cm

Answer:

7 mol.dm^3

Explanation:

formula for calculating concentration: C = n/v

Start by changing 5000ml solution to dm^3 because volume is in dm^3

1 ml = 1cm^3

then from a cm^3 to dm^3 you divide by 1000

5000ml = 5000cm^3

5000÷1000= 5dm^3

c = n/v

= 35/5

= 7mol.dm^3

Answer:

Maybe later, not right now. Tell you when.

hot cheetos hot cheetossss

A direct current power supply of low voltage (less than 10 volts) has lost the markings that indicate which output terminal is positive and which is negative. A chemist suggests that the power supply terminals be connected to a pair of platinum electrodes that dip into 0.1-molar KI solution.  Only (B) A gas will be evolved only at the negative electrode correctly identifies the polarities of the power supply terminals.

When the power supply terminals are connected to a pair of platinum electrodes dipping into a 0.1-molar KI solution, the electrolysis of the solution will occur. In the process of electrolysis, the positive electrode (anode) attracts negatively charged ions (anions) and the negative electrode (cathode) attracts positively charged ions (cations).

In this case, when a gas is evolved, it indicates that reduction is occurring at the electrode. The gas evolved will be hydrogen gas (H₂) from the reduction of H⁺ ions in the KI solution.

Since hydrogen gas is evolved only at the negative electrode (cathode), the correct identification of the polarities of the power supply terminals is that a gas will be evolved only at the negative electrode.

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Answer:

Argon

Explanation:

Because, it is positioned down on the periodic table

Answer:

Argon

Explanation:

Answer:

A

Explanation:

the answer is A because when your working cooperative people are helping you and non cooperative is where people are working against you by them selves

The free energy change (ΔG°) for the reaction of 2.46 moles of H2S(g) at standard conditions and 298K is approximately 252 kJ.G° for this reaction is expected to be less than zero.

The equilibrium constant (Keq) for a reaction is related to the standard Gibbs free energy change (ΔG°) through the equation:

ΔG° = -RTln(Keq)

Where:

ΔG° is the standard Gibbs free energy change

R is the gas constant (8.314 J/(mol·K))

T is the temperature in Kelvin (298 K)

ln is the natural logarithm

Given that Keq = 8.47×10^(-37), we can calculate the standard Gibbs free energy change (ΔG°) using the equation above:

ΔG° = - (8.314 J/(mol·K)) * (298 K) * ln(8.47×10^(-37))

Calculating this value gives us:

ΔG° = - (8.314 J/(mol·K)) * (298 K) * (-87.24)

ΔG° ≈ 2.52 × 10^5 J/mol

Converting the units to kilojoules (kJ/mol), we get:

ΔG° ≈ 252 kJ/mol

The free energy change (ΔG°) for the reaction of 2.46 moles of H2S(g) at standard conditions and 298K is approximately 252 kJ. Since the value of ΔG° is positive, it indicates that the reaction is not spontaneous and requires an input of energy to proceed.

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The density of the metal is 2.7 g/cm³, which can be used to identify the metal since different elements have different densities.

The given mass of the metal is 27g and its volume is 10 cm³.

The identity of the metal can be found out by using the formula of density, which is Density = Mass/Volume.

Density is a physical property of matter that is the amount of mass per unit volume. By rearranging the formula of density, we can determine the identity of the metal by finding its density which is given by mass divided by volume.

Identity of a metal that has a mass of 27g and a volume of 10 cm³ can be determined by using the formula of density which is Density = Mass/Volume.  

Here is the solution:Given,Mass of the metal = 27gVolume of the metal = 10 cm³

Density of the metal is given by the formula:Density = Mass/Volume

Substituting the given values in the formula:Density = 27g/10 cm³ = 2.7 g/cm³

The periodic table can be used to match the density with known elements and thus determine the identity of the metal.

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Answer: A. AgBr: pH would have little to no effect on its solubility.

B. LiF: pH would have little to no effect on its solubility.

C. Ca(OH)2: more soluble in a basic solution.

D. FeI3: more soluble in an acidic solution.

Explanation:)

Solubility of AgBr, LiF, Ca(OH)2, FeI2 based on acidic, basic, or neutral pHThe pH of the solution has an effect on the solubility of several compounds. Salts of weak acids or bases dissolve more in a basic or acidic environment, respectively, than in neutral water.

On the other hand, salts of strong acids and bases are mostly soluble in water and are not affected by the pH of the solution. The solubility of the given compounds will be affected as follows:AgBr: AgBr will dissolve more in an acidic solution because it is an ionic compound of a weak acid HBr. The equation for the dissociation of HBr is HBr⇌H+ + Br-. When the pH is reduced, H+ concentration increases, leading to the reaction moving to the left, ultimately resulting in the formation of more HBr. LiF: LiF is a salt of a strong acid (hydrofluoric acid) and a strong base (lithium hydroxide). Its solubility will not be affected by pH since it is mostly soluble in water.Ca(OH)2: Calcium hydroxide is a salt of a strong base (calcium oxide) and a strong acid (water). Its solubility will not be influenced by pH since it is mostly soluble in water.FeI2: Iron (II) iodide is an ionic compound with a weak acid (HI) and a strong base (Fe(OH)2). Its solubility would increase in an acidic environment. Since I- is a weak conjugate base of HI, the equation for the dissociation of HI would shift to the left in the presence of H+ ions in the acidic solution. Hence FeI2 will dissolve more in an acidic environment.

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Calculate the percentage composition of Ca(MnO4)2.

Firstly, we see how many atoms are there for each element in the formula.

Ca= 1 atom

Mn= 2 atoms

O= 8 atoms

Next, we are going to consult our periodic table for the atomic mass of each element.

Ca= 40

Mn= 55

O= 16

Then, we have to find the molar mass for the compound..

Here is the formula for calculating molar mass of an element:

Molar Mass= ( no. of atoms of the element × atomic mass of the element)

Now, we have to calculate the atomic mass of the compound. So using the molar mass formula for an element, we calculate the molar mass for each element then we sum up their molar masses to get the compounds molar mass.

Molar mass (Ca)= 1× 40

(Ca)= 40

Molar mass (Mn)=2×55

(Mn)= 110

Molar mass (O)= 8×16

(O)= 128

Now: Molar mass( compound)= (Ca)+(Mn)+(O)

= 40+ 110 128

= 278

This is everything we need to calculate our percentage composition for each element..

* The example says to find the percentage composition for Ca. So we only find for Ca, Which is already done using the formula and the answer is 14.39%.

To prove that your answer is correct, find the percentage composition for Mn and O as well. Then you add up their percentage compositions.

If you do and you get 100 as your answer, then your percentage compositions are correct.

Why don't you try finding the percentage composition for Mn and O, then add up all the three percentage compositions. If you 100 as their sum, then your percentage composition for each of the elements are correct.