A car travels 75 mi/hr. How many hours will it take to travel 837 km? (Pick the answer closest to the correct answer,

1.61 km=1 mile)

Answers

Answer 1

Answer:

6.9 hours

Explanation:

In order to solve this problem we'll convert 837 km to miles (another option would be to convert 75 mi/hr to km/hr). To make said conversion we'll use the given conversion factor:

837 km * [tex]\frac{1mi}{1.61km}[/tex] = 519.88 mi

Finally we calculate the time required to travel said distance at a constant speed of 75 mi/hr:

519.88 mi ÷ 75 mi/hr = 6.9 hr
Answer 2

The amount of time it would take to travel 837 km is equal to 7 hours.

Given the following data:

Speed = 75 mi/hr.Distance = 837 km.

To determine the amount of time it would take to travel 837 km:

How to calculate time.

First of all, we would convert the value of the distance in kilometers to miles as follows:

Conversion:

1.61 km = 1 mile

837 km = X mile.

Cross-multiplying, we have:

[tex]X=\frac{837}{1.61}[/tex]

X = 519.88 miles.

Mathematically, time is given by this formula:

[tex]Time = \frac{distance}{speed}[/tex]

Substituting the given parameters into the formula, we have;

[tex]Time = \frac{519.88}{75}[/tex]

Time = 6.93 7 hours.

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Related Questions


A car changes its velocity from 0 m/s to 14 m/s in 2 seconds.
What is the acceleration

Answers

Answer:

7

Explanation:

You divide the 14m/s by 2 and get the answer of the acceleration of 7

Scientists classify rocks mainly according to which feature?

their color

how they form

their hardness

where they are found

Answers

Their color is the main reason to classify according to the scientist.

can someone please help me asap ill mark u brainlest

Answers

Answer:It is the ground state of NA

Ground state of NA! Have a good day

Which of the following are true about an atom? Choose all that apply.

Answers

Answer:

Explanation:

Atoms are the building blocks of matter.

They are the smallest particles of an element that still have the element's properties.

All atoms are very small, but atoms of different elements vary in size.

Three main types of particles that make up all atoms are protons, neutrons, and electrons.

On the basis of the information above, a buffer with a pH = 9 can best be made by using

A pure NaH2PO4

B H3PO4 + H2PO4–

C H2PO4– + PO42–

D H2PO4– + HPO42–

E HPO42– + PO43

Answers

Answer:

D H2PO4– + HPO42–

Explanation:

The acid dissociation constant for [tex]\mathbf{H_3PO_4 , H_2PO^{-}_4 , HPO_4^{2-}}[/tex] are [tex]\mathbf{7\times 10^{-3}, \ \ 8\times 10^{-8} ,\ \ 5\times 10^{-13}}[/tex] respectively.

[tex]\mathbf{pka (H_3PO_4) = -log (7\times 10^{-3} )=2.2}[/tex]

[tex]\mathbf{pka (H_2PO_4^-) = -log (8\times 10^{-8} )=7.1}[/tex]

[tex]\mathbf{pka (HPO_4^{2-}) = -log (5\times 10^{-13} )=12.3}[/tex]

The reason while option D is the best answer is that, the value of pKa for both

[tex]\mathbf{H_2PO^{-}_4 ,\ \& \ HPO_4^{2-}}[/tex] lies on either side of the desired pH of the buffer. This implies that one is slightly over and the other is slightly under.

Using Henderson-Hasselbach equation:

[tex]\mathbf{pH = pKa + log \Big( \dfrac{HPO_4^{2-}}{H_2PO_4^-} \Big)}[/tex]

The compounds that are used for the formulation of the pH 9 buffer are [tex]\rm H_2PO_4^-\;and\;HPO_4^+[/tex]. Thus, option D is correct.

The buffers are the solutions of acids and base of appropriate pH, that are able to limit the change in pH in the reaction mixture.

Which compound is used for pH 9 buffer?

The buffer pH is adjusted with the compounds that has been able to add base or acid to the solution.

For the formulation of buffer of specific pH, the acid and base solutions are required.

The compounds that are used for the formulation of the pH 9 buffer are [tex]\rm H_2PO_4^-\;and\;HPO_4^+[/tex], as they are able to provide acid and base to the solution.

Thus, option D is correct.

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A tank contains 10 liters of pure water. A solution of an unknown, but constant concentration of salt is flowing in at 0.5 liters per minute. The water is mixed well and drained at 1 liter per minute. After 20 minutes there are 10 grams of salt in the tank. (i) Give an adequate mathematical model for this scenario. Explain what each of your variables means. (ii) What is the concentration of the incoming salt solution

Answers

Answer:

i) ∴∫[tex]\frac{dA}{A}[/tex]  = ∫ [tex]\frac{-1}{10} dt[/tex] ------ ( 1 )

ii) C = 4.303

Explanation:

Given data:

water in tank = 10 liters

concentration of salt flowing in = 0.5 liters/min

10 grams of salt is left in tank after 20 minutes

mixed water is drained at 1 liter per minute

i) Adequate mathematical model for the scenario

lets assume ; A( t ) amount of salt after t minute

A( t ) = 10grams   where t = 20 minutes

differentiate A(t)

dA / dt = ( rate in ) - ( rate out )

           = 0.5 * 0  - A/10

∴∫[tex]\frac{dA}{A}[/tex]  = ∫ [tex]\frac{-1}{10} dt[/tex] ------ ( 1 )

ii) hence;  In A = [tex]\frac{-1}{10} t + C[/tex]  -----  ( 2 )

at  t = 20 , A = 10grams

find C = In 10 + 2

          = 2.303 + 2 = 4.303

back to ( 2 )

In A = [tex]\frac{-t}{10} + 4.303[/tex]

∴ A = e [tex]\frac{-t}{10} + 4.303[/tex]

Ethane is a hydrocarbon with a formula of C2H6 . How many Carbon and Hydrogen atoms are contained within 3 molecules of ethane ?

Answers

Answer:

Within three molecules of Ethane, it would have 6 carbon, and 18 hydrogen atoms in it.

Explanation:

Determine the empirical and molecular formulas of the mandelic acid​

Answers

Answer:

Both empirical and molecular are C₈H₈O₃.

Explanation:

Hello!

In this case, according the attached picture, it is possible to figure out the molecular formula of the mandelic acid by counting each carbon, hydrogen and oxygen in the molecule.

In such a way, we can see the presence of eight carbon atoms, eight hydrogen atoms and three carbon atoms; thus, the molecular formula is:

C₈H₈O₃

Furthermore, since the empirical formula is the smallest representation of the molecular formula when we are able to simplify it, we evidence no simplification is possible, consequently, the empirical formula equals the molecular one.

Best regards!

help! help! plz give 4 different between orbit and orbital​

Answers

Answer:

Differences between Orbit and Orbitals

Orbit

An orbit is the simple planar representation of an electron.

It can be simply defined as the path that gets established in a circular motion by revolving the electron around the nucleus

The shape of molecules cannot be explained by an orbit as they are non-directional by nature.

An orbit that is well-defined goes against the Heisenberg principle.

Orbital

An orbital refers to the dimensional motion of an electron around the nucleus in a three-dimensional motion.

An orbital can simply be defined as the space or the region where the electron is likely to be found the most.

The shapes of the molecules can be found out as they are directional by nature.

An ideal orbital agrees with the theory of Heisenberg’s Principles.

An aqueous solution of nitric acid is standardized by titration with a 0.174 M solution of barium hydroxide. If 13.9 mL of base are required to neutralize 28.7 mL of the acid, what is the molarity of the nitric acid solution?

Answers

Answer:

Explanation:

2HNO₃ + Ba( OH)₂ = Ba( NO₃ )₂ + 2H₂O .

2 mole      1 mole

13.9 mL of .174M barium hydroxide contains .0139 x .174 moles

= 2.42 x 10⁻³ moles .

1 mole of barium hydroxide reacts with 2 moles of nitric acid

2.42 x 10⁻³ moles of barium hydroxide will react with 2 x 2.42 x 10⁻³ moles of nitric acid

= 4.84 x 10⁻³ moles

4.84 x 10⁻³ moles of nitric acid is contained in 28.7 mL

molarity of nitric acid = 4.84 x 10⁻³ / 28.7 x 10⁻³

= .169 M .

Name the compound AgF

Answers

Answer: Silver (I) fluoride molecule · AgF

Classification: Inorganic compound (Could be salt)

Ionic compound (Silver is a metal)

Valence of F (F must form an octet): 7

Valence of Ag: 11

Total valence electrons: 18

Molar mass: 126.87 g/mol

 

Explanation:

does warm air or cool air hold more humidity.​

Answers

Answer:

warm

Explanation:

warm air holds more humidity

Find the mass of 2.40 moles of CO. gas..

Answers

Got a pic of the sheet???

La fórmula molecular del pentano y del nonano son​

Answers

Nose jajajajajaj si mr ayudas te ayudo

A hydrogen atom is removed from the first carbon atom of a butane molecule and is replaced by a hydroxyl group.

Required:
Draw the new molecule formed.

Answers

Answer:

See answer below

Explanation:

In this case, let's draw the butane molecule:

CH₃ - CH₂ - CH₂ - CH₃

According to what the exercise states, we removed an atom of hydrogen from the frist carbon. This could be any of the terminals. I'll grab the first from left to right.

CH₂⁺ - CH₂ - CH₂ - CH₃

When this happens, the atom of carbon is lacking one space and it forms a carbocation.

Followed this step, an hydroxile group replace the atom of hydrogen. The hydroxile is the OH, and when we have an alkane with an OH group in the molecule, we are actually converting this molecule into an alcohol, therefore the molecule formed is:

OH - CH₂ - CH₂ - CH₂ - CH₃

Hope this helps

Steam is collected and observed to condense into liquid water. Which of the following would you expect to observe if a thermometer recorded the temperature of the substance?

SELECT AN ANSWER

The temperature would decrease.


The temperature would remain the same.


It would depend on the amount of steam.


The temperature would increase.

Answers

the water will be increased

According to the graph, what is the instantaneous speed of the object at 5 seconds? *

Captionless Image
4 m/s
7 m/s
0.25 m/s
3 m/s

Answers

nooooOoOOOOOɪᴏᴏɪᴡᴏᴏɪʀᴇᴡʜʜʙᴠᴇᴠᴅᴊʜʙsʙʙsʙʙᴊᴊᴊᴊʀvesebhreeje

Answer:4m/s

Explanation:The reason why that the answer is because I am Smart.

If 0.64 mol PCl5 is placed in a 1.0 L flask and allowed to reach equilibrium at a given temperature, what is the final concentration of Cl2 in the flask?

PCl5 (g)→ PCl3 (aq) + Cl2 (g) Kc= 0.47

Answers

Answer: The final concentration of [tex]Cl_2[/tex] at equilibrium is 0.36 M

Explanation:

Moles of  [tex]PCl_5[/tex] = 0.64 mole  

Volume of solution = 1.0 L

Initial concentration of [tex]PCl_5[/tex] = [tex]\frac{moles}{Volume}=\frac{0.64mol}{1.0L}=0.64 M[/tex]

The given balanced equilibrium reaction is,

                     [tex]PCl_5(g)\rightleftharpoons PCl_3(g)+Cl_2(g)[/tex]

Initial conc.       0.64 M         0M        0M  

At eqm. conc.     (0.64-x) M   (x) M      (x) M

The expression for equilibrium constant for this reaction will be,

[tex]K_c=\frac{[Cl_2]\times [PCl_3]}{[PCl_5]}[/tex]  

Now put all the given values in this expression, we get

[tex]0.47=\frac{(x)\times (x)}{(0.64-x)}[/tex]

By solving the term 'x', we get :

x = 0.36

Thus, the final concentration of [tex]Cl_2[/tex] at equilibrium is x = 0.36 M

The concentration of Cl2 is 0.36M.

Number of moles of PCl5 = 0.64 mol

Volume =  1.0 L

Concentration of PCl5 = 0.64 mol/1.0 L  = 0.64  M

The equation of the reaction is;

          PCl5 (g)→ PCl3 (aq) + Cl2 (g)

I         0.64            0                0

C       -x                 +x               +x

E     0.64 - x           x                  x

Kc = [PCl3] [Cl2]/[PCl5]

0.47 = x^2/0.64 - x

0.47(0.64 - x) =  x^2

0.3 - 0.47x =x^2

x^2 +  0.47x - 0.3 = 0

x = 0.36 M

The concentration of Cl2 is 0.36M.

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Describe how moving the mountain lions could affect the ecosystem

Answers

Answer:

If Mountain lions are removed from a habitat/ecosystem, their prey will overpopulate, which may lead to extinctions on the pray of the secondary consumers. ex. A mountain lion would eat rabbits who eat berries, if there are no mountain lions to kill the rabbits, then the berries may be scarce

Explanation:

bc i know everthing

The yield for a particular well is 280 gallons per minute (gpm). Of the drawdown for this well is 23 feet, what is the specific yield in gpm/ft?

Answers

Answer:

[tex]Y=12.2 \frac{gpm}{ft}[/tex]

Explanation:

Hello!

In this case, since we can find that the well produces 280 gpm, and the given drawdown is 23 ft, we need to divide 280 by 23 to obtain the yield in gmp/ft as shown below:

[tex]Y=\frac{280gpm}{23ft} \\\\Y=12.2 \frac{gpm}{ft}[/tex]

Best regards!

Look at sample problem 19.10 in the 8th ed Silberberg book. Write the Ksp expression. Find the concentrations of the ions you need (in this case Ca2 and F-). Put those concentrations into the Ksp expression to calculate Q. Compare Q to K A common laboratory method for preparing a precipitate is to mix solutions containing the component ions. Does a precipitate form when 10. ml of 0.0010 M Ca(NO3)2 is mixed with 10. ml of 0.00010 M NaF

Answers

Answer:

Explanation:

From the information given:

[tex]CaF_2 \to Ca^{2+} + 2F^-[/tex]

[tex]Ksp = 3.2 \times 10^{-11}[/tex]

no of moles of [tex]Ca^{2+}[/tex] = 0.01 L × 0.0010 mol/L

no of moles of [tex]Ca^{2+}[/tex] = [tex]1 \times 10^{-5} \ mol[/tex]

no of moles of [tex]F^-[/tex] = 0.01 L × 0.00010 mol/L

no of moles of [tex]F^-[/tex] = [tex]1 \times 10^{-6}\ mol[/tex]

Total volume = 0.02 L

[tex][Ca^{2+}}] = \dfrac{1\times10^{-5} \ mol}{0.02 \ L} \\ \\ \\ \[[Ca^{2+}}] = 0.0005 \ mol/L[/tex]

[tex][F^{-}] = \dfrac{(1\times 10^{-6} \ mol)}{0.02 \ L}[/tex]

[tex][F^{-}] = 5 \times 10^{-5} \ mol/L[/tex]

[tex]Q = [Ca^{2+}][F^-]^2 \\ \\ Q = 0.0005 \times (5\times 10^{-5})^2 \\ \\ Q = 1.25 \times 10^{-12}[/tex]

Since Q<ksp, then there will no be any precipitation of CaF2

You and your family are on vacation in the mountains. You are trying to locate the campsite where you will be staying but you cannot get a signal. What is one reason why your GPS is not responding.

Answers

Answer:

A satellite may be malfunctioning.

Line of sight may be blocked.

low batteries in your GPS.

Write the line notation for a cell in which the cell reaction is as follow
H2 + I2 = 2 HI

Answers

Answer:

I2(g)/I^-(aq)//H2 (g)/H^+(aq)

Explanation:

Let us remember that in every redox reaction, a specie is oxidized and a specie is reduced.

This means that one specie looses electrons while the other species gains electrons.

Considering the overall reaction; H2 + I2 = 2 HI

Oxidation half equation;

H2 (g) ------> 2H^+(aq) + 2e

Reduction half equation;

I2(g) + 2e ------> 2I^-(aq)

Line notation;

I2(g)/I^-(aq)//H2 (g)/H^+(aq)

Prokaryotic cell division is a___________process involving onc chromosom.

A. simple
B. complex
C. unusual

Answers

Answer:

It’s is a simple

Explanation:the prokaryotic cell involves a simple process which intern involves one chromosom

50 POINTS
Which of the following correctly describes a compound?

A. The atoms are bonded together, and the compound has different physical and chemical properties than the individual elements.
B. The atoms have no set ratio for how the atoms can combine, and they are not chemically bonded together.
C. The atoms can only combine in fixed ratios, and they retain their individual chemical and physical properties.
D. The atoms retain their individual chemical properties, and they can only be separated from each other by a chemical change.

Answers

Answer: A chemical compound can be described as substance composed of atoms from more than one element held together by chemical bonds in a fixed stoichiometric proportion. A compound has different physical and chemical properties from its constituent elements.

For example : compound water is made up of H and O bonded together and it has different properties from O and H.

Thus, among the given options, the one coreectly describing a compound is

a) The atoms are bonded together, and the compound has different physical and chemical properties than the individual elements.

. Which state of matter has a defined volume but no defined shape?
HELPPPP PLEASE FAST

Answers

Answer:

liquid

Explanation:

it's not plasma, solid, or gas

so I think liquid

The answer would be A liquid

What happens to algae when the temperature in the ocean becomes too hot?
O The algae are susceptible to infection.
O The algae become pale.
O The algae photosynthesize faster.
O The algae lose their ability to photosynthesize

Answers

Answer:

The algae lose their ability to photosynthesize.

Explanation:

Because the algae turn the energy from the sunlight into chemicals.

Hoped this helped!

A sample of 0.600 mol of a metal M reacts completely with excess fluorine to form 46.8 g of MF2.?
a) How many moles of F are in the sample of MF2 that forms? (1.20 mol F)
b) How many grams of M are in this sample of MF2?
c) What element is represented by the symbol M? (Ca)

Answers

Answer:

See Explanation

Explanation:

Given:

moles M = 0.600 mole

moles F = excess (for rxn stoichiometry)

Formula Weight (F.Wt.) of F = 19 grams/mole (from Periodic Table)

Yield in grams = 46.8 grams (assuming theoritical yield)

Rxn:         M          +        F₂       =>   MF₂

         0.600mol         Excess          0.600mol (1:1 rxn ratio for M:MF₂)

a. moles of F in MF₂ = 2(0.600) moles F = 1.2 moles F

b. mole weight MF₂ = 46.8g/0.600mol = 78g/mole

    F.Wt. MF₂ = F.Wt. M + 2(F.Wt. F)

     => mass M = F.Wt. M = [F.Wt. MF₂ - 2(F.Wt. F)] = 78g/mol. - 2(19g/mol.)

     = (78 - 38) grams/mole = 40 grams/mole

c. Calcium (Ca) has F.Wt. = 40 grams/mole (compared to Calcium on Periodic Table.

From the question, the metal is the limiting reactant and must be used to obtain the required results which are;

a) There are 1.20 mol F in MF2.

b) There are 40g of M in MF2.

c) M is calcium.

From the reaction equation;

M + F2 ----> MF2

Since the reaction is 1:1, 0.600 mol of MF2 is formed

Note that 1 mole of MF2 contains two moles of F and one mole of M

Hence, number of moles of F in MF2 = 2 *  0.600 mol = 1.20 mol F

Since 1 mole of M is contained in MF2, there are 0.600 moles of M in MF2.

If 1 mol of M forms 1 mole of MF2

And, 0.600 mol of M form 0.600 mol of MF2

Number of moles of MF2 = mass/molar mass

Number of moles of MF2 =  0.600 mol

Mass of MF2 formed = 46.8 g

Molar mass of MF2 = mass/Number of moles of MF2

Molar mass of MF2 = 46.8 g/0.600 mol

Molar mass of MF2 = 78 g/mol

Molar mass = Sum of Relative atomic mass of component atoms.

Hence;

78 = M + 2(19)

M = 78 - 2(19)

M = 40 g

The element must be calcium

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Which word best describes the relationship between polyps and algae
exoskeletal
Bleached
Photosynthetic
Symbiotic

Answers

Answer:

symbiotic

Explanation:

There like a close friendship

Write the word equation for
the reaction between sodium
hydrogen carbonate and
sulfuric acid.

Answers

Answer:

NaHCo3+Na2So4---Nna2So4+H2O+CO2

Answer:

sodium two sulphate+Carbondioxed gas +water

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In Mendels day, many people thought that offspring inherited a blend of their parents traits. For example, they thought that an animal with white fur and an animal with black fur would produce offspring with grey fur. This is called the blending theory of inheritance. How did Mendel show that the blending theory was incorrect? when HCl react with finely powdered iron it form ferrous chloride and not ferric chloride. why? True or False:The day after the accident at Chernobyl, the city next to itwent about their day like normal.O TrueO False What is Bingham's MAIN purpose in "The Annexation of Hawaii"? . to raise international awareness of desire to remain independent to inspire support among Americans for the annexation of Hawaii B. To inspire support among Americans for the annexation of HawaiianC. to warn other nations against claiming the Hawaiian Islands for themselves D to explain to Hawaiian islanders why annexation would be beneficial an ionic bond consist of a gas and metal Translate We are lazier than they into Spanish in the box below: 1. In a capitalist system, *5 pointsA. the government makes all the decisionsB. individuals and private businesses make their own decisionsC. the dictator controls the economyD. the people vote on economic decisions2. Under a communist system *5 pointsA. a single party rules politics and makes economic decisionsB. individual achievements are highly valued.C. people work togetherD. there are many classes in society3. The Soviets blocked all the roads into Berlin because *5 pointsA. the US, Britain, and France wanted to separate Germany into 4 zonesB. the Marshall Plan was createdC. the UN was createdD. the US, Britain, and France wanted to reunite the German zones4. After World War 2 ended, Japan's government became *5 pointsA. communistB. like Great Britain's governmentC. a dictatorshipD. part of NATO5. Following the policy of containment, the US aimed to *5 pointsA. support capitalismB. help returning veteransC. keep communism from spreadingD. identify communists living in the US6. Claims that communist spies were working in the US government were made by *5 pointsA. Richard NixonB. Alger HissC. Harry TrumanD. Joseph McCarthy7. Which of the following sentences explains the communists' victory in the Chinese Civil War? *5 pointsA. The people believed the Nationalists were corrupt.B. The Chinese people were tired of fighting.C. The people were influenced by the US.D. The people were influenced by the Soviet Union.8. When the fighting ended in the Korean War, *5 pointsA. North and South Korea were divided at the 38th Parallel.B. A communist government was established in South Korea.C. China gained control of the peninsulaD. 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Summer Sage, Inc. starts the year with a cumulative favorable temporary difference (due to accelerated depreciation) of $100,000. During the year, the enacted tax rate on Summer Sage increases from 35% to 40%; however, book and tax depreciation are equal and the cumulative temporary difference does not change. What journal entry must Summer Sage record for deferred taxes this year round 34 1/8 to the nearst whole number Describe two motivations of the Jamestown colonists for settling in the new world. The definition of symbiotic is O Having tiny tentaclesO consisting of two oxygen atomsO having a hard external coveringO living in close association A local banks advertising reads: "Give us $50,000 today, and well pay you $800 every year forever." If you plan to live forever, what annual interest rate will you earn on your deposit?1.92%1.60%2.56%2.24% Preliminary interviews are only required for the highest paying positions.True or False? 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