Is putting popsicle molds in the fridge a physical or a chemical change?
Explain why?

Hey there!:

[ H⁺ ] = [tex]10^{-pH}[/tex]

[H⁺ ] = [tex]10^{-1.9}[/tex]

[ H⁺ ] = [tex]1.26*10^{-2} M[/tex]

Hope that helps!

The concentration of hydroxide ion of unknown acid is [tex]\boxed{7.9344 \times {{10}^{ - 13}}\;{\text{M}}}[/tex]

Further Explanation:

An acid is a substance that has the ability to donate [tex]{{\text{H}}^ + }[/tex] ions or can accept electrons from the electron-rich species. The general dissociation reaction of acid is as follows:

[tex]\text{HA}}\to{{\text{H}}^+}+{{\text{A}}^-}[/tex]

Here, HA is an acid.

The acidic strength of an acid can be determined by pH value. The negative logarithm of hydronium ion concentration is defined as pH of the solution. Lower the pH value of an acid, the stronger will be the acid. At [tex]25\;^\circ {\text{C}}[/tex], pH value of an acid is less than 7.

The formula to calculate pH of acid is as follows:

[tex]{\text{pH}} = -\log\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^+}}\right][/tex]                                              

Here,

[tex]\left[ {{{\text{H}}_3}{{\text{O}}^ + }} \right][/tex] is the concentration of hydronium ion.

The relation between the concentration of hydronium ion and hydroxide ion is as follows:

[tex]\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^+}}\right]\left[{{\text{O}}{{\text{H}}^ - }}\right] = {10^{ - 14}}[/tex]                                              

Here,

[tex]\left[ {{{\text{H}}_3}{{\text{O}}^ + }} \right][/tex] is the concentration of hydronium ion.

[tex]\left[ {{\text{O}}{{\text{H}}^ - }} \right][/tex] is the concentration of hydroxide ion.

Given information:

The pH value of unknown acid is 1.9.

To calculate:  

The hydroxide ion concentration of unknown acid.

Solution:

Step 1: Initially, we have to calculate the concentration of hydronium ion by using equation (1).

The formula to calculate pH of the unknown acid is as follows:[tex]{\text{pH}} =  - \log \left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right][/tex]                

                                                    ...... (1)

Rearrange the equation (1) to calculate the concentration of hydronium ion.

[tex]\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right] = {10^{ - {\text{pH}}}}[/tex]          

                                           ...... (2)                                                  

Substitute 1.9 for pH in the equation (2).

[tex]\begin{gathered}  \left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right] = {10^{ - 1.9}} \\    = 1.2589 \times {10^{ - 2}}\;{\text{M}} \\ \end{gathered}[/tex]

Step 2: The concentration of hydronium ion calculated in step (1) can be used to calculate the concentration of  [tex]{\text{O}}{{\text{H}}^ - }[/tex] ions by using the relation (3).

The relation between the concentration of hydronium ion and hydroxide ion is as follows:

[tex]\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right]\left[ {{\text{O}}{{\text{H}}^ - }} \right] = {10^{ - 14}}[/tex]                       ...... (3)

Rearrange the equation (3) to calculate the concentration of hydroxide ion.

[tex]\left[ {{\text{O}}{{\text{H}}^ - }} \right] = \frac{{{{10}^{ - 14}}}}{{\left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right]}}[/tex]                    ...... (4)

Substitute [tex]1.2589 \times {10^{ - 2}}[/tex] for  \left[ {{{\text{H}}_{\text{3}}}{{\text{O}}^ + }} \right] in the equation (4).

[tex]\begin{gathered}  \left[ {{\text{O}}{{\text{H}}^ - }} \right] = \frac{{{{10}^{ - 14}}}}{{1.2589 \times {{10}^{ - 2}}}} \\    = 7.9434 \times {10^{ - 13}}\;{\text{M}} \\ \end{gathered}[/tex]

Learn more:

1. The reason for the acidity of water https://brainly.com/question/1550328

2. Reason for the acidic and basic nature of amino acid. https://brainly.com/question/5050077

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Acids, bases, and salts

Keywords: pH, acid, pOH, base, hydronium ion, hydrogen ion, hydroxide ion, acidic nature, and basic nature.

theyre fossils, when extinct beings such as dinosaurs died their bones would sometimes get stuck in clay or amber (i cant remember if theres any other types of rock) or sediment) and stay there for years and years then scientist called Paleontologists find them and study them. hope this helps:)

Answer:

What is meant by extinct How do scientists obtain information about extinct species?

How do scientists obtain information about extinct species? A species is extinct if no members of that species are still alive. Most of what scientists know about extinct species is based on the fossil record. What are mass extinctions?

Explanation:

Carbon:

Protons: 6

Neutrons: 7

Electrons: 6 (in a neutral atom)

Hope that helps:)

Yes, this is a balanced chemical equation, and it obeys the Law of Conservation of Mass.

A balanced chemical equation obeys the Law of Conservation of Mass if there are the same numbers of each type of atom on each side of the reaction arrow.

2H₂ + O₂ ⟶ 2H₂O

Let’s check the numbers.

Atom On the left On the right

  H             4                 4

  O             2                 2

We have the same numbers of H and O atoms on each side of the reaction arrow.

The equation is balanced and it obeys the Law of Conservation of Mass.

Rusting ability is a chemical property.

Since the act of rusting creates a new material (an oxide), it is a chemical change.  The other three are physical properties, since they do not involve the formation of a new substance.

Rutherford's gold-foil experiment showed that D. the atom is mostly empty space.

When he shot α particles at a thin gold foil, most of them went straight through the foil without being deflected.

However, a few of the α particles were deflected by rather large angles. He concluded that the atom is mostly empty space with almost all its mass concentrated in a small central nucleus.

Do you want to know the times

Answer:

The answer is Dissemination of components controlled by electron design.  

Explanation:

the Aufbau rule, the Pauli rejection guideline, and Hund's rule,tell you how to discover the electron designs of particles. As indicated by the aufbau standard, electrons possess the orbitals of most reduced vitality first, Pauli-prohibition rule, and Hund's Rule. The electronic setup of cations is doled out by evacuating electrons first in the peripheral p orbital, trailed by the s orbital lastly the d orbitals.

The release or absorption of energy indicates a chemical change. (Option C).

A chemical change, also known as a chemical reaction, is a process in which one or more reactants are transformed into new substances (products) with different chemical properties.

During a chemical change, the arrangement of atoms is altered, resulting in the formation of new chemical bonds and the breaking of existing ones.

This process often involves the release or absorption of energy in the form of heat, light, or other forms of energy.

Thus, the release or absorption of energy indicates a chemical change.

Option C is the correct answer.

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Hey There!

p-aminophenol (109.13 g/mol) + Ac2O (102.09 g/mol) ---> acetominophen (151.16 g/mol)

next, since you already know your limiting reactant (p-aminophenol), convert it to mols  :

0.130 g / (109.13 g/mol) = 0.00119 moles

now that's your theoretical max, since its a 1:1 mol ratio, so multiply by the new molecular weight. :

0.00119  * 151.16  = 0.180 g

Hope that helps!

The theoretical yield of acetaminophen is equal to 1.19 × 10⁻³ mol.

The amount of a product obtained from a chemical reaction is expressed as the yield of the reaction. The amount of product predicted by stoichiometry is known as the theoretical yield, whereas the actual quantity obtained is called the actual yield.

Given the mass of the p-aminophenol = 0.130 g

The reaction between the p-aminophenol and acetic anhydride gives acetaminophen and acetic acid. As given the acetic anhydride is in excess, therefore, p-aminophenol will decide the amount of acetaminophen.

The molar mass of p-aminophenol = 109.13 g/mol

The number of moles of p-aminophenol = 0.130/109.13  = 1.19 × 10⁻³ mol

Therefore, 1.19 × 10⁻³ mol of acetaminophen will be formed.

The molar mass of the acetaminophen = 151.16 g/mol

The mass of the acetaminophen =  1.19 × 10⁻³ × 151.16 = 0.18 g

Therefore, the theoretical yield of acetaminophen is 1.19 × 10⁻³ moles.

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As learned in an earlier unit, free fall is a special type of motion in which the only force acting upon an object is gravity. Objects that are said to be undergoing free fall, are not encountering a significant force of air resistance; they are falling under the sole influence of gravity.

Hello!

In this chemical equation, there are two main elements. Those elements are magnesium (Mg) and oxygen (O).

Molecules are a group of atoms bonded together, and in this case, the oxygen molecules is O2, but not 2MgO because there are two different molecules in this compound.

Coefficients are a number that multiply an entire molecule, and are also placed in front of it. In this case, O2 has no coefficient, but a subscript of 2. But, every molecule in this equation must have a coefficient and if add a coefficient of 1 to the oxygen molecule, it does nothing to the overall balancing of equations.

Therefore, the coefficient to the oxygen molecule is choice C, 1.

We have that It is seen from the equation that the Number or variable that Precedes the Oxygen atom is 1

Option C

From the question we are told

in this equation 2mg+o2=2mgo what is the coefficient to the oxygen molecule  

A,2  

B,4  

C,1  

D,0

Generally

Coefficient of a molecule is the digit, Number or variable that precedes the Molecule

Therefore

It is seen from the equation that the Number or variable that Precedes the Oxygen atom is 1

Option C

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Answer : Equation A represents a synthesis reaction, and equation B represents a combustion reaction.

Explanation :

A : [tex]H_2+Cl_2\rightarrow 2HCl[/tex]

Equation A is a synthesis reaction in which the two reactants combine to form a single product.

B : [tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]

Equation B is a combustion reaction in which the a hydrocarbon react with an oxygen to give carbon dioxide and water a s a product.

Hence, the equation A represents a synthesis reaction, and equation B represents a combustion reaction.

From the illustration, the type of reaction represented by equation A would be a synthesis reaction while that of B would be a combustion reaction.

In synthesis reactions, two or more atoms of different elements or molecules come together to form a product. In equation A, H2 and Cl2 come together to form HCl. Thus, A is a synthesis reaction.

In combustion reactions, substances react in oxygen to generate new products, usually accompanied by light and the generation of heat. In equation B, CH4 reacts with O2 to produce CO2 and H2O with the production of heat. Thus, B is a combustion reaction.

More on different types of reactions can be found here: https://brainly.com/question/20479735

Answer:- [tex]1.76*10^-^2[/tex] g of carbon dioxide.

Solution:- The balanced equation for the combustion of methane is:

[tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]

There is 1:1 mol ratio between methane and carbon dioxide.  Grams of methane are converted to moles and then using mol ratio we get the moles of carbon dioxide that could further be converted to grams. The calculations are shown as:

[tex]6.40*10^-^3gCH_4(\frac{1molCH_4}{16gCH_4})(\frac{1molCO_2}{1molCH_4})(\frac{44gCO_2}{1molCO_2})[/tex]

= [tex]1.76*10^-^2gCO_2[/tex]

So, complete combustion of given amount of methane gives [tex]1.76*10^-^2gCO_2[/tex] .

Answer: The penetrating rays and particles given off by radioactive materials is called radiation.

Explanation:

The penetrating rays and particles given off by radioactive materials is called radiation.

An element which readily degenerates its nucleus and emits alpha particles, beta particles and gamma rays is called a radioactive element.

For example, uranium, actinium, thorium etc are all radiactive elements.

Answer:

lepords

Explanation:

The correct answer is: An example of an organism that is not an example of symbiosis would be a predator-prey relationship where the interaction is not obligatory for either species' survival.

Symbiosis is a close and long-term interaction between two different biological organisms. There are three main types of symbiosis: mutualism, commensalism, and parasitism. In mutualism, both species benefit from the interaction. In commensalism, one species benefits while the other is neither harmed nor benefited. In parasitism, one species, the parasite, benefits at the expense of the other, the host.

A predator-prey relationship, such as a lion hunting a zebra, is typically not considered symbiosis because it is usually a short-term interaction and not obligatory for the survival of either species. While both species are involved in an ecological interaction, the relationship is not symbiotic in the sense that it does not meet the criteria of being a close, long-term interaction that is essential to the survival of either species. Each species can potentially find other sources of food, and the interaction does not necessarily occur over a significant portion of the organisms' life spans.

 In contrast, examples of symbiosis include:

- The relationship between clownfish and sea anemones, which is a case of mutualism where the clownfish gains protection from predators among the anemone's tentacles, and the anemone benefits from the clownfish's waste as nutrients and the clownfish's defense against anemone predators.

- The relationship between barnacles attached to whales, which is commensalism, as the barnacles get transportation and access to food without significantly harming or benefiting the whale.

- The relationship between tapeworms and their hosts, which is parasitism, as the tapeworm lives in the host's intestine and absorbs nutrients from the host's diet, causing harm to the host.

 Therefore, a predator-prey relationship like that of a lion and a zebra is not an example of symbiosis because it lacks the necessary characteristics of a close, long-term, and obligatory interaction for the survival of the involved species."

The new weight of the graduated cylinder after adding 57.0 mL of water is 140.2 g.

To determine the new weight of a graduated cylinder after adding water, we need to consider the mass of the water added. The step by step solution is as follows:

Total Mass = 83.2 g (graduated cylinder) + 57.0 g (water) = 140.2 g

Thus, the graduated cylinder now weighs 140.2 g.

Answer: The particles move faster and spread further apart

Explanation:

The region of the atom where protons and neutrons are located (B) is called the nucleus.

The region of the atom where electrons are located (A) is called orbits.

An atom is made up of electrons in orbits and protons and neutrons in the nucleus.

In the atom, there is an innermost part where we find the subatomic particles called neutrons and protons. This region of the atom is called the nucleus. Most of the mass of the atom is concentrated here.

The electrons are found to move round this nucleus in circular paths called orbits.

In the figure, label A refers to orbits while label B refers to the nucleus.

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Answer:

1st is Nucleus and 2nd is Orbitals

Explanation:

For the first question the answer is

The "s" orbital can only hold a maximum of two electrons. ... Elements in the each group have the same number of valence electrons. Why is hydrogen set apart by itself? Hydrogen does not belong to a single group b/c it can be considered an alkali metal, but it is also a gas.

1. Hydrogen is set apart by itself due to its unique properties that do not fit neatly into any specific group in the periodic table. 2. The alkali metals have similar valence electron configurations, each having one valence electron in their outermost energy level. 3. The alkaline-earth metals are less reactive than the alkali metals because they have two valence electrons in their outermost energy level, requiring more energy to lose them. 4. The transition metals belong to groups 3 to 12 in the periodic table, characterized by partially filled d orbitals in their electron configurations. 5. The halogens, belonging to group 17, share common properties like having 7 valence electrons, high reactivity, and forming acidic compounds when combined with hydrogen.

1. Hydrogen is set apart by itself because it does not fit neatly into any specific group in the periodic table. It has unique properties that are distinct from both the alkali metals and the halogens. While it can form positive ions like the alkali metals, it can also gain an electron to form negative ions like the halogens. Additionally, hydrogen can form covalent bonds with other elements, unlike the alkali metals and halogens. Due to these differences, hydrogen is considered a non-metal and is placed separately at the top of the periodic table.

2. The valence electron configurations of the alkali metals are similar as they all have one valence electron in their outermost energy level. For example, lithium has a valence electron configuration of 2s¹, sodium has 3s¹, potassium has 4s¹, and so on. This single valence electron makes the alkali metals highly reactive, as they readily lose it to form positive ions, achieving a stable electron configuration.

3. The alkaline-earth metals are less reactive than the alkali metals because they have two valence electrons in their outermost energy level. These electrons are held more tightly by the nucleus compared to the single valence electron of alkali metals. As a result, alkaline-earth metals require more energy to lose their valence electrons and become positive ions. While they are still reactive, they are not as reactive as the alkali metals.

4. The transition metals belong to groups 3 to 12 in the periodic table. These elements have partially filled d orbitals in their electron configurations, which gives them unique properties, such as forming colored compounds, being good conductors of electricity, and having high melting and boiling points. They are often used as catalysts in chemical reactions due to their ability to undergo multiple oxidation states.

5. The halogens have several properties in common. They belong to group 17 of the periodic table and have 7 valence electrons in their outermost energy level. Halogens are highly reactive non-metals, and they readily gain one electron to achieve a stable electron configuration. They have high electronegativity, making them strong oxidizing agents. Halogens exist as diatomic molecules in their elemental form (e.g., Cl₂, Br₂, I₂) and have a characteristic color and odor. Additionally, they form acidic compounds when combined with hydrogen, such as hydrochloric acid (HCl) and hydrofluoric acid (HF).

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Answer:

Carbon is the basis of all living things

Nitrogen is found in certain foods

Oxygen and hydrogen combine with each other to form water

Carbon, oxygen, hydrogen, nitrogen, phosphorus and sulfur are found in organic compounds

Explanation:

We are all made up of mainly three elements, Carbon, Hydrogen, and Oxygen. These three elements are found in every living organism on our planet, and along with a few trace elements, they make up all the nutrients we take in and use to build our bodies and survive.

Nitrogen is primarily found in meats, and this is because nitrogen is a key element in amino acids (which are used to build proteins), however we cannot directly assimilate nitrogen from the air, so we have to assimilate it through amino acids already synthesized in plants, or in proteins found in meat.

The chemical formula for water is H₂O. Seeing the chemical formula, it is obvious that hydrogen and oxygen are the only elements in the water molecule.

In our bodies, we use phosphorus to form our skeleton and help maintain it, sulfur and nitrogen can be found in some amino acids, and carbon, hydrogen and oxygen can be found in carbohydrates, lipids and proteins.

Answer:

Carbon is the basis of all living things

Nitrogen is found in certain foods

Oxygen and hydrogen combine with each other to form water

Carbon, oxygen, hydrogen, nitrogen, phosphorus and sulfur are found in organic compounds

Explanation:

LOL FREE POINTS

Hey there!

Moles of stock solution:

47.0 mL in liters : 47.0 / 1000 => 0.047 L

n = M * V

n = 0.400 * 0.047

n = 0.0188 moles

Volume final :

M = n / V

0.100 = 0.0188 / V

V = 0.0188 / 0.100

V = 0.188 L =>  188 mL

Therefore Watter added :

volume final - volume initial

188 mL - 47.0 mL =>  141 mL

Hope That helps!

Final answer:

The statement that all moving objects have momentum is true because momentum is a product of an object's mass and velocity, both of which are non-zero for moving objects.

Explanation:

The statement that all moving objects have momentum is true. Momentum is the product of an object's mass and velocity and is given by the equation p = mv, where p is momentum, m is mass, and v is velocity. Since any object that is moving has a velocity greater than zero and a non-zero mass, it will indeed have momentum. Additionally, momentum is a vector quantity, which means it has both magnitude and direction, and it is measured in kilograms meters per second (kg·m/s).

To further elucidate, let's consider the Law of Conservation of Momentum, which states that in a closed system, the total momentum remains constant unless acted upon by an external force. Therefore, if two objects collide and come to rest, as mentioned in the problem, the momentum is not lost but transferred, ensuring the total momentum before and after the collision is the same.

With $14.12, and a price of $3 per pound, you can buy 4 pounds of pecans, which equates to 508 pecans, since each pound has 127 pecans.

To determine how many pecans can be bought for $14.12, we need to calculate the number of pounds that can be purchased and then multiply by the number of pecans per pound. The given price is $3 per pound, and there are 127 pecans per pound.

First, divide the total amount of money by the price per pound:

$14.12 ÷ $3.00 = 4.7067 pounds

Since you cannot purchase a fraction of a pecan, we need to find the maximum whole number of pounds that can be bought with $14.12, which is 4 pounds. Multiplying this number by the number of pecans per pound gives the total number of pecans that can be bought:

4 pounds × 127 pecans/pound = 508 pecans

Therefore, you can buy 508 pecans for $14.12.

Answer:

B. the amount of heat required to increase the temperature of 1 gram by 1°C

Explanation:

The heat required by a substance having mass m to raise the temperature of it by ΔT.

Q = m c ΔT

where c is the specific heat of the substance.

[tex] c = \frac{Q}{m\Delta T}[/tex]

Specific heat for a substance is the amount of heat required to increase the temperature of 1 gram by 1°C.

For example, the specific heat capacity of water is 4.186 J/g°C. This means 4.186 J is required to raise the temperature of 1 g of water by 1°C.

Solution:

molarity= [tex]\frac{\text{moles}}{\text{volume in litres}}[/tex]

(a) Molarity of NaOH, [tex]M_1[/tex]= 0.03020 M

Volume of NaOH added,[tex]V_1[/tex]= 32.60 mL= 0.0326 L

(1L= 1000mL)

Number of moles of NaOH added :

0.03020 M NaOH means 1L of solution contains 0.03020 moles 0.0326 L contains =[tex]0.03020\times 0.0326[/tex] = 0.00098 moles

(b) Equal number of moles of acid  will neutralize equal number of moles of base, thus we can apply molarity equation:

Molarity of citric acid, [tex]M_2[/tex]=?

volume of citric acid, [tex]V_2[/tex]= 20 mL= 0.02 L

using formula, [tex](M_1)(V_1)=(M_2)(V_2)[/tex] ,

[tex]M_2= \frac{(M_1)(V_1)}{(V_2)}[/tex]

[tex]M_2= \frac{(0.03020 M)(0.0326 L)}{(0.02 L)}[/tex] = 0.049 M

(c) Grams of citric acid in 20 ml

moles of citric acid = [tex]{M_2}\times V_1[/tex] of solution in Liters = [tex]0.049 \times 0.02[/tex] = 0.00098 moles

Mass of citric acid =[tex]\text{moles}\times \text{Molecular} mass[/tex]

[tex]= 0.00098\times 192.12[/tex] = 0.1882 g

(d) 20 mL solution of ginger ale contains of citric acid

[tex]0.1882 g= 0.1882 \times 1000 mg[/tex] = 188.2 mg (1g = 1000mg)

Since, 20 mL solution of ginger ale contains of citric acid 188.2 mg

so 1 mL of solution contains = [tex]\frac{188.2 mg}{20 mL}[/tex]

                                              = 9.41 mg/ mL

(a)

Molarity = moles of solute / liter of solution

Moles of solute = molarity x liter of solution  

Molarity of NaOH = 0.03020 M

Liter of solution = 32.60 mL / 1000 = 0.0326 L

Moles of NaOH = 0.03020 M x 0.0326 L = 9.85 x 10⁻⁴ moles

(b)

The reaction between NaOH and citric acid is as follows:

C₃H₅O(COOH)₃ + 3NaOH → Na₃C₃H₅O(COO)₃ + 3H₂O

As the balanced chemical equation 3 moles of NaOH reacts with 1 mole of citric acid (Na₃C₃H₅O(COO)₃)

Since the moles of NaOH is 9.85 x 10⁻⁴ the moles of citric acid will be (9.85 x 10⁻⁴) / 3 or  3.284 x 10⁻⁴ moles.

Therefore, the moles of citric acid is  3.284 x 10⁻⁴

(c)

Moles = Mass/ Molar mass

Mass = Moles x Molar mass

Moles of citric acid = 3.284 x 10⁻⁴

Molar mass of citric acid = 192.124 g/mol

Mass of citric acid = 3.284 x 10⁻⁴ x 192.124 g/mol =

Therefore, the mass of citric acid is 0.0631 g

(d)

Mass of citric acid = 0.0631 g

1 g = 1000 mg

Therefore, mass of citric acid = 0.0631 x 1000 = 63.1 mg

(e)

Given,

Volume of citric acid = 20.0 mL

20 ml of citric acid has a mass of 63.1 mg

Therefore, miligram per militier = 63.1 mg/20 ml = 3.155 mg/ml

It would roughly be 16,404 feet. Or if you wanted to be more specific 16,404.2. I hope this helps.

Easiest way is dimensional analysis.

[tex]5km * \frac{3280.84ft}{1km} = 16404.2[/tex]