Cual es la formula universal de
Zn - Zn +2
2 Ag - 2
2 Ag

se oxida y cual se reduce

Answers

Answer 1
t gn bjjjkknnnkkm
explanation:

Related Questions

How many unpaired electrons are in the following complex ions?
a. Ru(NH3)62+ (low-spin case)
b. Ni(H2O)62+
c. V(en)33+

Answers

Solution :

A complex ion may be defined as a metal ion that is located at the center with other molecules or ions surrounding the center ion.

In the context, the number of the unpaired electrons for the following complex ions are :

1. [tex]$Ru(NH_3)62+$[/tex]  (low spin)

  [tex]$Ru^{2+} = [Kr] \ 4d^6 \ 5s^0$[/tex]

   Here all the d-electrons are paired. Therefore, there are no unpaired electrons.

2. [tex]$Ni(H_2O)62+$[/tex]  (high spin)

   [tex]$Ni^{2+} = [Ar] \ 4s^0 \ 3d^8$[/tex]

   Therefore, it has two unpaired electrons.

3. [tex]$V(en)33+$[/tex]  (high spin)

    [tex]$V=[Ar] \ 3d^2 \ 4s^0$[/tex]

   It has 2 unpaired electrons

n-hexane boils at 68.7 oC at 1.013 bar and the heat of Vaporization is 28850
J/mol. Calculate Its Entropy ?

Answers

He one 28850




C. C c c.

What mass of sucrose is needed to make 300.0 mL of a 0.5 M solution? (molar mass=
342.34 g/mol)

Answers

i need points i’m sorry but yea lol good luck

A silver bar with a specific heat of 0.235J/gºC has a mass of 250.g and is heated from 22.0°C to 68.5°C. How much heat will the silver bar absorb?​

Answers

Answer:

2731.875 J

Explanation:

Applying

Q = cm(t₂-t₁)................ Equation 1

Where Q = amount of heat, c = specific heat capacity of silver, m = mass of silver, t₂ = Final temperature of silver, t₁ = Initial temperature of silver

From the question,

Given: c = 0.235 J/g°C, m = 250 g, t₁ = 22.0°C, t₂ = 68.5°C

Substitute these values into equation 1

Q = 0.235×250(68.5-22.0)

Q = 58.75(46.5)

Q = 2731.875 J

How many grams of carbon are In 25 g of CO2?

Answers

Answer: almost 7g

Explanation: 25 grams of carbon dioxide contains 6.818 grams of carbon.

when 18.0 g H20 is mixed with 33.5 g Fe, which is the limiting reactant?

Answers

Answer:

si.mple fe

Explanation:

ghhsshzhzbbzhh

What is the pH of a 6.2 x 10-5 M NaOH solution?

Answers

Answer:

4.21

Explanation:

The pH of a solution can be found by using the formula

[tex]pH = - log [ {H}^{+} ][/tex]

From the question we have

[tex]ph = - log(6.2 \times {10}^{ - 5} ) \\ = 4.207608[/tex]

We have the final answer as

4.21

Hope this helps you

A 16.0 L sample contains 0.80 moles of a gas. If the gas is at the
same pressure and temperature, what is the number of moles when
the volume increases to 24.0 L? NOTE: You must show your
calculation on the attached scratch paper, including which of the
Gas Law formulas you used. *
A. 0.83 mol
B. 1.2 mol
C. 0.53 mol
D. 1.9 mol
(Please show your work)

Answers

[tex]\huge\bf\red{\underline{\underline{Answer:-}}}[/tex]

Here, 16 L = 0.80 Mole

Or, 1 L = ( 0.80 / 16 ) Mole

Or, 1 L = 0.05 Mole

_____________________________

Now, 24 L = 0.05 × 24

= [tex] \frac{5}{100} \times 24[/tex]

= 120/100

= 12/10

= 1.2 Mole ( Ans )
B 1.2 mole should be your answer
hope this helps

What causes the recognition of an element from its energy signature?
O
A. Each element emits radiations at random frequencies.
B. Each element emits energy that can be transformed into sound.
C. Each element emits electromagnetic waves that travel faster than light.
D. Each element emits electromagnetic waves at a unique set of wavelengths.

Answers

Answer:

I'm so sorry if this is wrong but I think its B

Atomic number: 19 is what Chemical symbol?

Answers

Answer:

oficialismo hemostasia Jalisco

Answer:

K

Explanation:

Potassium is atomic no 19 and it is k because is from kalium, the Meldiaeval Latin for potash, which may have derived from an arabic word quality, meaning alkali.

Atomic mass, 39.098amu

Oxidation status, +1

Year discovered, 1807

Melting point, 63.28 degrees Celsius(145.90degrees Fahrenheit )

Boiling point, 760 degrees Celsius (1400 degrees Fahrenheit )

At the start of a reaction, there are 0.0249 mol N2,
3.21 x 10-2 mol H2, and 6.42 x 10-4 mol NH3 in a
3.50 L reaction vessel at 375°C. If the equilibrium constant, K, for the reaction:
N2(g) + 3H2(g)= 2NH3(g)
is 1.2 at this temperature, decide whether the system is at equilibrium or not. If it is not, predict in which direction, the net reaction will proceed.​

Answers

Answer:

Explanation:

The reaction is given as:

[tex]N_{2(g)} + 3H_{2(g)} \to 2NH_{3(g)}[/tex]

The reaction quotient is:

[tex]Q_C = \dfrac{[NH_3]^2}{[N_2][H_2]^3}[/tex]

From the given information:

TO find each entity in the reaction quotient, we have:

[tex][NH_3] = \dfrac{6.42 \times 10^{-4}}{3.5}\\ \\ NH_3 = 1.834 \times 10^{-4}[/tex]

[tex][N_2] = \dfrac{0.024 }{3.5}[/tex]

[tex][N_2] = 0.006857[/tex]

[tex][H_2] =\dfrac{3.21 \times 10^{-2}}{3.5}[/tex]

[tex][H_2] = 9.17 \times 10^{-3}[/tex]

[tex]Q_c= \dfrac{(1.834 \times 10^{-4})^2}{(0.0711)\times (9.17\times 10^{-3})^3} \\ \\ Q_c = 0.6135[/tex]

However; given that:

[tex]K_c = 1.2[/tex]

By relating [tex]Q_c \ \ and \ \ K_c[/tex], we will realize that [tex]Q_c \ \ < \ \ K_c[/tex]

The reaction is said that it is not at equilibrium and for it to be at equilibrium, then the reaction needs to proceed in the forward direction.

In 1773 Benjamin Franklin, investigating the calming effect of oil on the water of a pond near London, observed that a teaspoonful of oil would cover about half an acre of the surface. From this information, estimate the height or thickness of an oil molecule in the floating film of oil. Then estimate the cross sectional area of an oil molecule in the floating film You may assume that Franklin used a lamp oil, like camphene, C10H16.

Required:
Calculate the thickness (in nm) of the surface film and the surface area (in nm2) occupied by an oleic acid molecule on water.

Answers

Answer:

a. 2.44 nm

b. 15.33 nm²

Explanation:

a. Calculate the thickness (in nm) of the surface film

Since the volume of a teaspoon equals V = 4.93 cm³ and the area of the oil film is half an acre = 1/2 × 4046.86 m² = 2023.43 m²

The volume of the oil film, V' equals the volume of the oil in the teaspoon, V

V' = Ah where A = cross-sectional area of oil film = 2023.43 m² = 2023.43 × 10⁴ cm² and h = height of oil film

So, V' = V

Ah = V

h = V/A

= 4.93 cm³/2023.43 × 10⁴ cm²

= 0.00244 × 10⁻⁴ cm

= 2.44 × 10⁻⁷ cm

=  2.44 × 10⁻⁷ cm × 1m/100 cm

= 2.44 × 10⁻⁹ m

= 2.44 nm

b. The surface area (in nm2) occupied by an oleic acid molecule on water.

Since the height of the oil film equals the diameter of the oil molecule, and the molecule is assumed to be a sphere of radius, r. Its surface area is thus A = 4πr²

r = h/2 = 2.44 nm/2 = 1.22 nm

A = 4πr²

A = 4π(1.22 nm)²

A = 4.88π nm²

A = 15.33 nm²

chemical properties of citric acid​

Answers

Answer:

Citric Acid is a weak acid with a chemical formula C6H8O7.

...

Properties of Citric Acid – C6H8O7.

C6H8O7 Citric Acid

Molecular Weight/ Molar Mass 192.124 g/mol

Density 1.66 g/cm³

Boiling Point 310 °C

Melting Point 153 °C

Hope it helps❤️

Chemical formula: C6H8O7
Properties: No color, no smell, Crystal like appearance, Boiling point of 175 C, Melting point of 153 C, Density of 1.66 g/ml, Weak acid

If a drop of red dye is placed in the middle of a shallow dish of water, the dye will diffuse slowly and a red cloud of dye will grow larger with time.

a. True
b. False

Answers

Answer:

True

Explanation:

Diffusion is the movement of the particles of a substances from a region of higher concentration to a region of lower concentration.

Diffusion occurs in response to a concentration gradient.

In this case, the dye is at a higher concentration at the middle of the shallow dish of water. Diffusion causes the dye to spread out gradually thereby causing the red cloud to grow larger with time.

what is an example of a change in genetic traits of an organism do to human affect

Answers

Answer:

A person's skin color, hair color, dimples, freckles, and blood type are all examples of genetic variations that can occur in a human population.

Explanation:

A 0.750 M sample of phosphorus pentachloride decomposes to give phosphorus trichloride and chlorine gases.If the equilibrium concentration of PCl5 is 0.650M,what is the equilibrium constant for the reaction?
PCl5(g) --------> PCl3(g)+ Cl₂(g)
A) Keq = 0.0133
B) Keq = 0.0154
C) Keq = 0.133
D) Keq = 0.154
E) Keq = 65.0

Answers

Answer:

Explanation:

Amount of phosphorus pentachloride reacted = 0.75 M - 0.65 M = 0.10 M

PCl₅(g) --------> PCl₃(g)+ Cl₂(g)

1 mole               1 mole      1 mole

Amount of phosphorus pentachloride reacted = 0.75 M - 0.65 M = 0.10 M

PCl₃(g) and  Cl₂(g) formed are .10 M and .10 M

Keq = [ PCl₃] x [ Cl₂ ] / [ PCl₅ ]

= .10 M x .10 M / .65 M

= .0154

B ) is the correct choice .

0=4
Balance this equation
H₂sicl2+ H₂O → H8Si4O4 + HCl

Answers

Balanced Equation is

4H2SiCl2+4H2O → H8Si4O4 + 8HCl

how to solve x² in differential​

Answers

Answer:

x² = mutiphy by them self

Explanation:

Enthalpy change is the
a. amount of energy absorbed or lost by a system as heat during a process at constant pressure.
b. entropy change of a system at constant pressure.
c. pressure change of a system at constant temperature.
d. temperature change of a system at constant pressure.

Answers

Answer:

I believe is A

Explanation:

Enthalpy change is the name given to the amount of heat evolved or absorbed in a reaction carried out at constant pressure.

Please hurry!

Best answer gets Brainliest!!

Please answer the question ASAP

Scientists clarify an element based on what criteria

A)Atomic number

B)Mass number

C)Atomic mass

D)Atomic symbol

Answers

A) atomic number/ number of protons

Combustion of a 1.031-g sample of a compound containing only carbon, hydrogen,
and oxygen produced 2.265 g of CO2(g) and 1.236 g of H2O(g). What is the
empirical formula of the compound?
3 국
Molar masses in g/mol: CO2 = 44.01; H20 = 18.02; C = 12.01; H = 1.01
C3H50​

Answers

Answer:

C₃H₈O

Explanation:

From the question given above, the following data were obtained:

Mass of compound = 1.031 g

Mass of CO₂ = 2.265 g

Mass of H₂O = 1.236 g

Empirical formula =?

Next, we shall determine the mass of carbon, hydrogen and oxygen in the compound. This can be obtained as follow:

For carbon, C:

Mass of CO₂ = 2.265 g

Molar mass of CO₂ = 44.01 g/mol

Molar mass of C = 12.01 g/mol

Mass of C =?

Mass of C = molar mass of C / molar mass of CO₂ × mass of CO₂

Mass of C = 12.01/44.01 × 2.265

Mass of C = 0.618 g

For hydrogen, H:

Mass of H₂O = 1.236 g

Molar mass of H₂O = 18.02 g/mol

Molar mass of H₂ = 2 × 1.01 = 2.02 g/mol

Mass of H =?

Mass of H = Molar mass of H₂ / Molar mass of H₂O × Mass of H₂O

Mass of H = 2.02/18.02 × 1.236

Mass of H = 0.139 g

For oxygen, O:

Mass of compound = 1.031 g

Mass of C = 0.618 g

Mass of H = 0.139 g

Mass of O =?

Mass of O = Mass of compound – (mass of C + mass of H)

Mass of O = 1.031 – ( 0.618 + 0.139)

Mass of O = 1.031 – 0.757

Mass of O = 0.274 g

Finally, we shall determine the empirical formula. This can be obtained as follow:

C = 0.618 g

H = 0.139 g

O = 0.274 g

Divide by their molar mass

C = 0.618 / 12.01 = 0.051

H = 0.139 / 1.01 = 0.138

O = 0.274 / 16 = 0.017

Divide by the smallest

C = 0.051 / 0.017 = 3

H = 0.138 / 0.017 = 8

O = 0.017 / 0.017 = 1

Therefore, the empirical formula of the compound is C₃H₈O

Based on the data provided, the empirical formula of the compound is C₃H₈O

What is empirical formula?

The empirical formula of compound is its simplest formula showing the mole ratio of the elements in the compound.

First, the mass of carbon, hydrogen and oxygen in the compound is determined first as follows:

For carbon, C:

Mass of CO₂ = 2.265 g

Molar mass of CO₂ = 44.01 g/mol

Molar mass of C = 12.01 g/mol

Mass of C = 12.01/44.01 × 2.265

Mass of C = 0.618 g

For hydrogen, H:

Mass of H₂O = 1.236 g

Molar mass of H₂O = 18.02 g/mol

Molar mass of H₂ = 2 × 1.01 = 2.02 g/mol

Mass of H = 2.02/18.02 × 1.236

Mass of H = 0.139 g

For oxygen, O:

Mass of compound = 1.031 g

Mass of C = 0.618 g

Mass of H = 0.139 g

Mass of O = Mass of compound – (mass of C + mass of H)

Mass of O = 1.031 – ( 0.618 + 0.139)

Mass of O = 0.274 g

To determine the empirical formula of a compound, the mole ratio of the elements are determined as follows:

Mole ratio = reacting mass/molar mass

Mole ratio of the elements:

Carbon                Hydrogen         Oxygen

0.618 g/12.01    0.139 / 1.01         0.274 / 16

0.051                   0.138              0.017

Divide by the smallest ratio to convert to whole numbers

0.051 / 0.017     0.138 / 0.017  0.017 / 0.017

3           :            8           :               1

Therefore, the empirical formula of the compound is C₃H₈O

Learn more about empirical formula at: https://brainly.com/question/24297883

3.05 moles of H2O is equivalent to (blank amount) molecules of water.

Show your work.

Answers

Answer:

[tex]1 \: mole \: = 6.02 \times {10}^{23} \: molecules \\ 3.05 \: moles \: = (3.05 \times 6.02 \times {10}^{23} ) \: molecules \\ = 1.8361 \times {10}^{24} \: molecules[/tex]

Chemical bond stretching frequencies depend on two major factors, namely atomic weight and bond stiffness. The frequency absorbed is directly proportional to the bond strength (stiffness) but inversely proportional to the atomic weight. Which of the following bonds will give the highest absorption frequency value?
A. C single bond C.
B. C double bond C.
C. All would be the same frequency.
D. C triple bond C.

Answers

Answer:

D. C triple bond C.

Explanation:

The absorption frequency value is highest for carbon-carbon triple bond. The stretching frequencies are much higher than the bending frequency. It mainly depends upon the strength of the bonds as well as masses of the bonded atoms.

The triple bonds have higher stretching strength than the double bonds and double bonds have higher strength than single carbon to carbon bonds.

The triple bonds has a higher bond order, i.e. 3. So it has maximum stretching bonds.

Which of the following statement is true?

a. The resonance effect of the hydroxyl group stabiizes the anionic intermediate.
b. The resonance effect of the hydroxyl group stabilizes the cationic
c. The inductive effect of the hydroxyl group stabiizes the cationic intermediate
d. The inductive effect of the hydroxyl group stabiizes the anionic intermediate

Answers

Answer:

a. The resonance effect of the hydroxyl group stabilizes the anionic intermediate

Explanation:

The resonance effect stabilizes the the charge through the delocalization of the pi bonds. The resonance stabilization mainly occurs in the conjugated pi systems.

For example, phenol forms a strong hydrogen bonds than the nonaromatic alcohols as the [tex]$O_2-H_2$[/tex] dipole present in the hydroxyl group is being stabilized by the presence of the aromatic ring of phenol.

Thus the resonance effect of the hydroxyl group stabilizes the anionic intermediate.

A 3L sample of an ideal gas at 178 K has a pressure of 0.3 atm. Assuming that the volume is constant, what is the approximate pressure of the gas after it is heated to 278 K?

Answers

Answer: The approximate pressure of the gas after it is heated to 278 K is 0.468 atm.

Explanation:

Given: [tex]T_{1}[/tex] = 178 K,      [tex]P_{1}[/tex] = 0.3 atm

[tex]T_{2}[/tex] = 278 K,           [tex]P_{2}[/tex] = ?

According to Gay Lussac law, at constant volume the pressure of a gas is directly proportional to the temperature.

Formula used to calculate the pressure is as follows.

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

Substitute the values into above formula is as follows.

[tex]\frac{P_{1}}{T_{1}} = \frac{P_{2}}{T_{2}}\\\frac{0.3 atm}{178 K} = \frac{P_{2}}{278 K}\\P_{2} = 0.468 atm[/tex]

Thus, we can conclude that the approximate pressure of the gas after it is heated to 278 K is 0.468 atm.

The blending together of some genes is called:

Answers

Answer:

its called molding

Explanation:

What is the new volume of a 61 L sample at STP that is moved to 183 K and 0.60 atm?

Answers

Answer: The new volume of a 61 L sample at STP that is moved to 183 K and 0.60 atm is 54.63 L.

Explanation:

Given: [tex]V_{1}[/tex] = 61 L,      [tex]T_{1}[/tex] = 183 K,      [tex]P_{1}[/tex] = 0.60 atm

At STP, the value of pressure is 1 atm and temperature is 273.15 K.

Now, formula used to calculate the new volume is as follows.

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

Substitute the values into above formula as follows.

[tex]\frac{P_{1}V_{1}}{T_{1}} = \frac{P_{2}V_{2}}{T_{2}}\\\frac{0.60 atm \times 61 L}{183 K} = \frac{1 atm \times V_{2}}{273.15 K}\\V_{2} = 54.63 L[/tex]

Thus, we can conclude that the new volume of a 61 L sample at STP that is moved to 183 K and 0.60 atm is 54.63 L.

A container holds 40.0 mL of nitrogen at 30° C and at a constant pressure.
Find its volume if the temperature increases to 80° C?

Answers

Answer:

The correct answer is - 46.60 mL.

Explanation:

To find the volume of the gas at its new increased temperature we need to use Charl Law that shows the direct relationship between Volume and Temperature while Pressure remains constant.

V1 = 40 ml

T1  = 30 degree C + 273 = 303 K

V2  = ?

T2  = 80 degree C + 273 = 353 K

Charl Equation is:

V 1/T 1  =  V 2/ T 2

(V1) * (T2)/ T1= V2

placing value:

40*353/303 = V2

= 14120/303

Vf = 46.60 mL

When 155 g of water at 20 ᵒC is mixed with 75 g of water at 80 ᵒC, assuming no heat is

lost to the surrounding what is the final temperature of the water. (Specific heat capacity

of water is 4.18 J/°C·g)​

Answers

Answer:

39.57 °C

Explanation:

Applying,

Heat gain = Heat lost.

cm'(t₃-t₁) = cm(t₂-t₃)................. Equation 1

Where c = specific heat capacity of water, m = mass of the hotter water, m' = mass of the colder water, t₁ = initial temperature of the colder water, t₂ = initial temperature of the hotter water, t₃ = Final Temperature.

Equation 1 above can futher be simplified to

m'(t₃-t₁) = m(t₂-t₃)................. Equation 2

From the question,

Given: m' = 155 g, m' = 75 g, t₁ = 20 °C, t₂ = 80 °C

Substitute these values into equation 2

155(t₃-20) = 75(80-t₃)

Solve for t₃

155t₃- 3100 = 6000-75t₃

155t₃+75t₃ = 6000+3100

230t₃ = 9100

t₃ = 9100/230

t₃ = 39.57 °C

Assuming no heat is lost to the surrounding, the final temperature of the water is 39.57°C.

Given the following data:

Mass of water 1 = 155 gInitial temperature of water 1 = 20°CMass of water 2 = 75 gInitial temperature of water 2 = 80°CSpecific heat capacity of water = 4.18 J/g°C

To determine the final temperature of the water, assuming no heat is lost to the surrounding:

The quantity of heat lost by the water 1 = The quantity of heat gained by the water 2.

[tex]Q_{lost} = Q_{gained}\\\\m_1c\theta = m_2c\theta\\\\m_1\theta = m_2\theta\\\\m_1(T_2 - T_1) = m_2(T_3 - T_2)[/tex]

Substituting the given parameters into the formula, we have;

[tex]155(T_2 -20)=75(80-T_2 )\\\\155T_2 -3100=6000-75T_2\\\\155T_2 +75T_2=6000+3100\\\\230T_2=9100\\\\T_2=\frac{9100}{230}[/tex]

Final temperature = 39.57°C

Read more: https://brainly.com/question/6957411

Which molecule will have double bonds?
(4 Points)

Fluorine

Nitrogen

Hydrogen

Oxygen

Answers

I believe its oxygen
hope this helps
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At most terrestrial men fancied there might be other men upon Mars, perhaps inferior to themselves and ready to welcome a missionary enterprise. Yet across the gulf of space, minds that are to our minds as ours are to those of the beasts that perish, intellects vast and cool and unsympathetic, regarded this earth with envious eyes, and slowly and surely drew their plans against us. And early in the twentieth century came the great disillusionment.Yet so vain is man, and so blinded by his vanity, that no writer, up to the very end of the nineteenth century, expressed any idea that intelligent life might have developed there far, or indeed at all, beyond its earthly level. Nor was it generally understood that since Mars is older than our earth, with scarcely a quarter of the superficial area and remoter from the sun, it necessarily follows that it is not only more distant from time's beginning but nearer its end.The secular cooling that must someday overtake our planet has already gone far indeed with our neighbour. Its physical condition is still largely a mystery, but we know now that even in its equatorial region the midday temperature barely approaches that of our coldest winter. Its air is much more attenuated than ours, its oceans have shrunk until they cover but a third of its surface, and as its slow seasons change huge snowcaps gather and melt about either pole and periodically inundate its temperate zones. That last stage of exhaustion, which to us is still incredibly remote, has become a present-day problem for the inhabitants of Mars. The immediate pressure of necessity has brightened their intellects, enlarged their powers, and hardened their hearts. And looking across space with instruments, and intelligences such as we have scarcely dreamed of, they see, at its nearest distance only 35,000,000 of miles sunward of them, a morning star of hope, our own warmer planet, green with vegetation and grey with water, with a cloudy atmosphere eloquent of fertility, with glimpses through its drifting cloud wisps of broad stretches of populous country and narrow, navy-crowded seas.And we men, the creatures who inhabit this earth, must be to them at least as alien and lowly as are the monkeys and lemurs to us. The intellectual side of man already admits that life is an incessant struggle for existence, and it would seem that this too is the belief of the minds upon Mars. Their world is far gone in its cooling and this world is still crowded with life, but crowded only with what they regard as inferior animals. To carry warfare sunward is, indeed, their only escape from the destruction that, generation after generation, creeps upon them.What key idea does the text below suggest?The immediate pressure of necessity has brightened their intellects, enlarged their powers, and hardened their hearts. As their situation grew worse, their course became clear and they lost any compassion. The growing doom consumed all their power to confront it. Their immediate needs made them more intelligent than they had been before. Their intelligence gave them less compassion than less intelligent others. hey guys can you tell for writing enquiry letter how much paragraphs do we need to write . this is class 8 PLEASE HELP ME! THANK YOU :D A cylinder has a height of 10 ft and a volume of 25,456 ft.The radius of the cylinder is approximately ___ feet.Round your answer to the nearest whole number. HELP! Will give branliest!! Please hel p me. !!!!!!! I need the median. The First Three Terms Of A Sequence Are Given. Round To The Nearest Thousandth (If Necessary). 403,395, 387, . Find The 36Th Term. Which of the following is the secondary principle of proportion?O AccentO DepthO ScaleO Tension A woman has eight keys on a key ring, one of which fits the door she wants to unlock. Sherandomly selects a key and tries it. If it does not unlock the door, she randomly selects anotherkey from those remaining and tries to unlock the door with it. She continues in this manner untilthe door is unlocked. Let X be the number of keys she tries before unlocking the door, countingthe key that actually worked. Required:Find the expected number of keys she will try before she opens the door.