The following half-reaction can be balanced in acidic solution:
N2O5 --> NH4+
How many electrons appear in the balanced equation?
A. 13e-
B. 14e-
C. 16e-
D. 18e-

Answers

Answer 1

Answer:

None of them, answer seems to be 24 unless I messed up

Explanation:

How many electrons appear in the balanced equation

What the heck do they mean, do they mean transferred?

N2O5 --> NH4+

Left Side

N 5+  Electrons 2 in central shell, 5 in outer

O 2- Electrons 2 in central shell, 6 in outer

Right Side

H  1+ Electrons 1 in central shell

N 3- Electrons 2 in central shell, 5 in outer

Hmm, ok so need to balance the half equation first, this is a redox reaction.

Hmm, so it's going to be something like

H2 + N2O5 → NH + O3  

Step 1. Write down the unbalanced equation ('skeleton equation') of the chemical reaction. All reactants and products must be known. For a better result write the reaction in ionic form.

H2 + N2O5 → NH + O3  

Step 2. Separate the process into half reactions. A redox reaction is nothing but both oxidation and reduction reactions taking place simultaneously.

a) Assign oxidation numbers for each atom in the equation. Oxidation number (also called oxidation state) is a measure of the degree of oxidation of an atom in a substance (see: Rules for assigning oxidation numbers).

H02 + N+52O-25 → N-1H+1 + O03  

b) Identify and write out all redox couples in reaction. Identify which reactants are being oxidized (the oxidation number increases when it reacts) and which are being reduced (the oxidation number goes down). Write down the transfer of electrons. Carefully, insert coefficients, if necessary, to make the numbers of oxidized and reduced atoms equal on the two sides of each redox couples.

When one member of the redox couple is oxygen with an oxidation state of -2 or hydrogen with an oxidation state of +1, it is best to replace it with a water molecule.

O:3H+12O-2 → O03 + 6e-(O)

H02 → H+12O-2 + 2e-(H)

R:N+52O-25 + 12e- → 2N-1H+1(N)

c) Combine these redox couples into two half-reactions: one for the oxidation, and one for the reduction (see: Divide the redox reaction into two half-reactions).

O:3H+12O-2 + H02 → O03 + H+12O-2 + 8e-  

R:N+52O-25 + 12e- → 2N-1H+1  

Step 3. Balance the atoms in each half reaction. A chemical equation must have the same number of atoms of each element on both sides of the equation. Add appropriate coefficients (stoichiometric coefficients) in front of the chemical formulas to balance the number of atoms. Never change any formulas.

a) Balance all other atoms except hydrogen and oxygen. We can use any of the species that appear in the skeleton equations for this purpose. Keep in mind that reactants should be added only to the left side of the equation and products to the right.

O:3H+12O-2 + H02 → O03 + H+12O-2 + 8e-  

R:N+52O-25 + 12e- → 2N-1H+1  

b) Balance the charge. For reactions in an acidic solution, balance the charge so that both sides have the same total charge by adding a H+ ion to the side deficient in positive charge.

O:3H+12O-2 + H02 → O03 + H+12O-2 + 8e- + 8H+  

R:N+52O-25 + 12e- + 12H+ → 2N-1H+1  

c) Balance the oxygen atoms. Check if there are the same numbers of oxygen atoms on the left and right side, if they aren't equilibrate these atoms by adding water molecules.

O:3H+12O-2 + H02 + H2O → O03 + H+12O-2 + 8e- + 8H+  

R:N+52O-25 + 12e- + 12H+ → 2N-1H+1 + 5H2O  

Balanced half-reactions are well tabulated in handbooks and on the web in a 'Tables of standard electrode potentials'. These tables, by convention, contain the half-cell potentials for reduction. To make the oxidation reaction, simply reverse the reduction reaction and change the sign on the E1/2 value.

Step 4. Make electron gain equivalent to electron lost. The electrons lost in the oxidation half-reaction must be equal the electrons gained in the reduction half-reaction. To make the two equal, multiply the coefficients of all species by integers producing the lowest common multiple between the half-reactions.

O:3H+12O-2 + H02 + H2O → O03 + H+12O-2 + 8e- + 8H+| *3

R:N+52O-25 + 12e- + 12H+ → 2N-1H+1 + 5H2O| *2

O:9H+12O-2 + 3H02 + 3H2O → 3O03 + 3H+12O-2 + 24e- + 24H+  

R:2N+52O-25 + 24e- + 24H+ → 4N-1H+1 + 10H2O  

Step 5. Add the half-reactions together. The two half-reactions can be combined just like two algebraic equations, with the arrow serving as the equals sign. Recombine the two half-reactions by adding all the reactants together on one side and all of the products together on the other side.

9H+12O-2 + 2N+52O-25 + 3H02 + 24e- + 3H2O + 24H+ → 3O03 + 4N-1H+1 + 13H2O + 24e- + 24H+

Step 6. Simplify the equation. The same species on opposite sides of the arrow can be canceled. Write the equation so that the coefficients are the smallest set of integers possible.

2N+52O-25 + 3H02 → 3O03 + 4N-1H+1 + H2O


Related Questions

Calcium nitrate, Ca(NO3)2 , is a(n) ___________________.

element

compound

heterogeneous mixture

homogeneous mixture

Answers

Calcium Nitrate is a chemical compound, not a mixture.

How many grams are in 0.572 moles of glucose, C6H12O6

Answers

Answer:

103.00

Explanation:

1 mole of Glucose

6 C = 6 * 12 = 72 grams

12H = 12 * 1 = 12 grams

6O = 6 * 16 =96 grams

Total          = 180 grams

0.572 moles of Glucose

1 mol of glucose = 180 grams

0.572 mols of glucose = x

x = 0.572 * 180

x = 103.00 grams

how many moles of hydrogen will react with 40g oxygen

Answers

Answer: 2.5 moles

2H2 + O2 = 2H2O

This implies that 2 moles of oxygen is needed to react with one mole of oxygen to form 2 moles of water

It also implies that

2 moles of hydrogen requires 32 grams of oxygen

? moles of hydrogen would require 40 g of oxygen

2 x 40/32 = 2.5 moles

how does photosynthesis and respiration in plants influence the amount of co2 in the atmosphere during a year?

Answers

Answer:

An increase in the amount of CO2 well increase the rate of photosynthesis, Carbon dioxide concentration will directly affect the rate of photosynthesis as it is used in the photosynthesis reaction.Increased amount of CO2 will increase the rate of photosynthesis to a certain limit, after which a further increase in its amount will no longer increase the rate any further.

Hope this helps.

Cheers! :)

For neon, determine the moles and mass contained in a 29.9−L volume at a pressure of 481.1 torr at a temperature of 300.0 K.

Answers

Answer:

.7689 mol

15.516 g

Explanation:

Use the Ideal Gas Law, PV = nRT.

Make sure to use the correct ideal gas constant R. You can either put R in torr, or you can change the pressure to atm. I've just used the torr ideal gas constant.

481.1 torr * 29.9 L = n 62.364 LTorr/molK * 300 K

14384.89 = 18709.2n

n = .7689 mol

The molar mass of neon (remember that neon gas = Ne, it's not diatomic) is 20.18 g/mol from the periodic table.

.7689 mol * 20.18 g/mol = 15.516 g

Iodine-131 has a half-life of 8 days. How long would it take for the number of unstable nuclei in the sample to be reduced from 1,000 to 125?

Answers

Answer:

After one-half life: 16 mg

After 2-half lives: 8 mg

After 3-half lives: 4 mg

After 4-half lives: 2 mg

After 5-half lives: 1 mg

(5 half-lives) x (8 days/half-life) = 40 days  

or doing it the mathematical way:  Let z be the number of days to be found:

1 mg = 32 mg x (1/2)^(z / 8 days)  

1/32 = (1/2)^(z / 8 days)  

log (1/32) = (z / 8 days) x log (1/2)  

z / 8 days = log (1/32) / log (1/2)

z = 8 days x log (1/32) / log (1/2) = 40 days

Explanation:

Iodine-131 has a half-life of 8 days, then it would it take for the number of unstable nuclei in the sample to be reduced from 1,000 to 125 is 512 days.

How do we calculate total time?

Total time of the reduction of any substance from an initial concentration to a particular concentration will be calculated as:

T = (t)ⁿ, where

n = number of half lives

t = half life time = 8 days

1st half life: 1000 → 500

2nd half life: 500 → 250

3rd half life: 250 → 125

So number of half life times is 3. On putting values we get,

T = (8)³

T = 512 days

Hence total duration of time is 512 days.

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Which of the following is the conjugate base of HPO 2?
O A. H2P04
B. PO 3
C. H3PO4
O D. HAP04

Answers

Answer:

A. H2P04

Explanation:

You want to test the effect of water temperature on the rate of sugar
dissolution. Which of the following is an example of a controlled experiment
to test this?
A. The temperatures of five beakers of 250 mL of water are kept
constant, and 10 g of sugar is added to each beaker.
B. The temperatures of five beakers of 250 mL of water are varied,
and 10 g of sugar is added to each beaker.
C. The temperatures of five beakers of 250 mL of water are varied,
and 10 g of sugar is added to each beaker while three of the
beakers are stirred.
D. The temperatures of five beakers of 250 mL of water are varied,
and different amounts of sugar are added to each beaker.

Answers

A, the temperatures of the water, the size of the beaker and the amount of sugar added to each are being controlled.

Answer:B

Explanation:

You want different temperatures for each beaker but everything else the same

Help!!
Which of the following is a chemical reaction?

a. New atoms are formed when substances are mixed together
b. A solid material melts and becomes a liquid
c. Atoms of the reactants rearrange to form a new substance

Answers

Answer:

C-Atoms of the reactants rearrange to form a new substance

Explanation:

Answer:

The answer is A.

Explanation:

B. is called a physical reaction

And C. is just a rearrangement.

Hi. Please I need About 20 Questions on Grahams Law of diffusion. Optional : ( with solutions.) Any amount of questions ranging from 5 will be appreciated

Answers

Answer:

I have posted some questions I used when learning Graham's law of diffusion

Explanation:

i posted 16 questions

I hope it helps.

How many moles of neon (Ne) gas have a volume of 2.2 L and a pressure of
0.83 atm at 283 K?
(The universal gas constant is 0.0821 L.atm/mol.K.)
O A. 13 mol
O B. 0.11 mol
O C. 42 mol
O D. 0.079 mol

Answers

Answer:

D. 0.079 mol

Explanation:

This question involving the number of moles of neon (Ne) gas can be solved using the ideal gas law, also called the general gas equation.

The formula for the general gas equation is:

PV = nRT

Where;

P = pressure (atm)

V = volume (Litres)

n = amount of substance (mol)

R = ideal gas constant

T = temperature (K)

In this question, P is given as 0.83atm, V = 2.2L, R = 0.0821 L.atm/mol.K, T= 283K, n = ?

We calculate 'n' by making it the subject of the formula i.e.

PV= nRT

Divide both sides by RT, we have;

n = PV/RT

Hence, we input our values

n = 0.83 × 2.2 / 0.0821 × 283

n= 1.826 / 23.2343

n = 0.07859

Hence, n is approximately 0.079 mol

The Sunhawk, a car built by students at SUNY New Paltz, prompted Forbes Magazine to ask “Is The $250,000 Sunhawk theSolar Car of the Future?” These cars show the most advanced solar technology and vehicle construction.There are trade-offs involved in the use of solar powered cars. What one advantage of owning a solar car?

Answers

Answer:

The potential of energy availability at all locations where there is Sunlight

Explanation:

One advantage in owning a solar car is the potential of energy availability

The solar car source of energy is from the Sun which is readily available during the daytime where there is a clear sky. The energy from sunlight  is converted to to electrical energy by the photovoltaic cells on solar panels installed on the roof area of solar powered cars

The energy from the Sunlight is a form of renewable energy and therefore allows for better stability as well as the possibility of reuse of the energy

There are no emissions from the use of solar cars including noise, making the solar car very environmentally friendly.

Plz answer quickly with explanations. .....

Answers

Answer:

It would be gas b. The gas you are talking about is carbon dioxide and for the reaction to work the gas needs to be bubbled through into the lime water.

Explanation:

The carbon dioxide reacts with lime water which is a solution of calcium hydroxide to form the white precipitate of calcium carbonate CaCO 3.

Calculate Rations. A transformer has ten turns of wire on the input side and 50 turns of wire on the output side. if the input voltage is 120 V, what will the output voltage be?

Answers

Answer:

Output voltage = 600 V

Explanation:

Using the transformer equation which simply states that the ratio of the secondary to primary voltages in a transformer equals the ratio of the number of loops in their coils.

Number of input turns/Number of output turns = Voltage of input/voltage of output

10/50 = 120V/voltage of output

Voltage of output = 120 V/0.2

Voltage of output = 600 V

Which type of reaction is described by the following equation Na2O (s) + 2CO2 (g) + H2) (g) Produces 2 NaHCO3 (s)

Answers

Answer:

If the reaction is going from left to right it would be synthesis, if going right to left it would be decomposition.

Explanation:

Na2O (s) + 2CO2 (g) + H2O (g) = 2 NaHCO3 (s)

Left Side

Na = 2

O = 6

C = 2

H = 2

Right Side

Na = 2

O = 6

C = 2

H = 2

Ok so is balanced already, though initial equation in question had an error in regards to the left hand side the ) should have been an O.

Hmm

Na2O (s) + 2CO2 (g) + H2O (g) = 2 NaHCO3 (s)

If it was going from right to left would be decomposition

But going from left to right it would be synthesis

Liquid acetone is ______________.

A incompressible and has a definite shape.

B compressible and has definite volume.

C incompressible and has an indefinite shape.

D compressible and has an indefinite volume.

Answers

A is the answer maybe

Why arent the jaguars and sloths growing and thriving?

Answers

Answer:

Need more details to answer correctly.

Do you mean in general why are populations decreasing?

Well for jaguars this is due to poaching and deforestation.

For Sloths this is due to deforestation.

In an ecosystem, the jaguars and sloths  are not growing and thriving due to deforestation and poaching.

What is an ecosystem?

Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.

Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.

Learn more about ecosystem,here:

https://brainly.com/question/13979184

#SPJ2

How are electrons and positrons the same, and how are they different?

Answers

Answer:

A positron is the antimatter counterpart of an electron (also called anti-electron). ... The spin, a type of angular momentum carried by the electron and positron, is the same for both. However, the electron and positron have the opposite charge. The electron has a negative charge, and the positron has positive charge.

What might happen to global atmospheric carbon levels if the polar ice caps were to melt?

Answers

If the Arctic became completely ice-free and phytoplankton productivity levels were maintained, Arrigo and his colleagues calculated that the new carbon sink could in theory absorb an extra 160 million tonnes of carbon each year.

If the polar ice caps were to melt then it could lift the lid of a new carbon sink capable of soaking up carbon dioxide.

What happens if the polar ice caps melt?

If all the ice protecting Antarctica, Greenland, and mountain glaciers around the sector were to melt, sea degrees might upward push about 70 meters (230 ft). the sea might cowl all of the coastal towns. And the land place would decrease considerably. but many cities, inclusive of Denver, might live to tell the tale.

How do melting ice caps affect the ecosystem?

Melting ice reasons more warming.

because they are darker in the shade, the ocean and land take in more incoming solar radiation and then launch the warmth to the environment. This reasons more global warming. in this way, melting ice causes more warming and so extra ice melts.

Learn more about Global Warming at https://brainly.com/question/3553382

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why the renewable energy resource you chose is positive

Answers

Answer:

Renewable energy require less overall maintenance than generators that use traditional fuel sources. Renewable energy has numerous health and environmental benefits.

Explanation:

Crude oil is a miscible mixture of liquids that has many uses . During the refining process it is separes and used to produce aviation fuel diesel fuel and gasoline how should scientists separate crude oil based on its physical properties

Answers

Answer:

3 rd point will be the ans

What are the following equations for each:

1. Ratio of product concentrations reactant concentrations at equilibrium.

2. Ratio of partial pressures of products to partial pressures of reactants (for gas phase reactions only) at equilibrium

3. Ratio of products reactants for the reaction of a weak base with water at equilibrium.

4. The thermodynamic equilibrium constant, calculated from thermodynamic data, not concentrations.

5. The autoionization constant for water (= 1.0 x 10-14).

6. Ratio of products reactants for the reaction of a weak acid with water at equilibrium

Answers

Answer: thats alot of reading

Explanation:

An electrical company charges 15 p per unit of energy (kWh).
Calculate the cost of running a 500 W freezer for a day. Show your working.

Answers

Answer:

180 p

Explanation:

Energy refers to the capacity of doing work.

Amount charged by an electrical company = 15 p per unit of energy (kWh)

As 1 W = 1000 kW,

[tex]500W=\frac{500}{1000}kW=0.5\,kW[/tex]

Also, 1 day = 24 hours.

Cost of running a 500 W freezer = 0.5 kW freezer for 1 hour = [tex]15\times 0.5=7.5\,p[/tex]

Therefore,

cost of running a 0.5 kW freezer for a day ( 24 hours ) = [tex]7.5\times 24=180\,p[/tex]

Amount charged by an electrical company = 15 p per unit of energy (kWh)

As 1 W = 1000 kW,

[tex]500W=\frac{500}{1000}kW=0.5\,kW[/tex]

Also, 1 day = 24 hours.

Cost of running a 500 W freezer = 0.5 kW freezer for 1 hour = [tex]15\times 0.5=7.5\,p[/tex]

Therefore,

cost of running a 0.5 kW freezer for a day ( 24 hours ) = [tex]7.5\times 24=180\,p[/tex]

Please help me out on this question!!

Answers

Answer:

Water H2O

Explanation:

A solvent is defined as being able to dissolve other substances, the fertilizer is being dissolved in the water prior to watering the plants, therefore the water is the solvent in this case.

The compound diborane can be used as a rocket propellant. What is the percent composition of boron in diborane (B2H6)? A. 22% B. 25% C. 39% D. 75% E. 78%

Answers

Answer: E. 78%

Explanation:

Diborane (B2H6), a chemical compound made up of approximately 78% Boron and 22% Hydrogen.

Answer:

E

Explanation:

#edmentumgang

What types of substances are considered drugs?​

Answers

Answer:

Marijuana

Opiates

Opioids

Explanation:

Can some one please help?
Neutralization Reactions
PREDICT THE PRODUCTS OF THE FOLLOWING REACTIONS
HNO3+ Ba(OH)2
+
+
H3PO4 + Ca(OH)2
HCI + FelOH)3 –

Answers

Answer:

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

H3PO4 + Ca(OH)2 = Ca3(PO4)2 + 6H2O

3HCl + Fe(OH)3) = FeCl3 + 3H2O

Explanation:

H+

N3-

O2-

Ba2+

OH-

P 5+, 3+, 3-

Ca2+

Cl-

Fe  2+, 3+

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

H3PO4 + Ca(OH)2 = Ca3(PO4)2 + 6H2O

3HCl + Fe(OH)3) = FeCl3 + 3H2O

what happens to the grass molecules when it is eaten by the zebra?

Answers

Answer:

read below

Explanation:

When the zebra eats grass, it gets energy from the sun that has been stored in the grass. Similarly, the lion obtains energy stored in the zebra. The zebra and lion both obtain the sun's energy indirectly from the energy that the grass obtained through photosynthesis.

Answer/Explanation:

It gets energy from the sun that was inside of the grass.

It happens like this:

Sun gives energy to grass, grass gives energy to zebra.

Sun ---> Grass ---> Zebra

PLEASE HELP ASAP!!!! 15PTS

How are 2,2-butanediol and 2,3,4-pentanetriol similar? Pick two.

EXPLANATION
2,2-butanediol is a four carbon chain with two hydroxyl groups both on the second carbon. 2,3,4-pentanetriol is a five carbon chain with three hydroxyl groups; one on carbon 2,3 and 4.

SELECT ALL THAT APPLY

Neither contain a hydroxyl group on an end chain carbon.


Neither contain four carbons in the parent chain.


Both contain a hydroxyl group on the second carbon.

Answers

Answer:

Both contain a hydroxyl group on the second carbon.

Neither contain a hydroxyl group on an end chain carbon.

Explanation:

2,2-butanediol Formula: C4H10O2

2,3,4-pentanetriol Formula: C5H12O3

Both contain a hydroxyl group on the second carbon.

Neither contain a hydroxyl group on an end chain carbon.

ASAP plz I will give the brainliest

Which type of bond describes the coming
together and sharing of two unpaired outer
electrons, one from each atom?
a. Single covalent bond
b. Double covalent bond
С. Triple covalent bond
d. lonic bond


2nd question
What is the name of this molecule (CO2) that
forms by burning of fuels and is one of the
gases that contributes to global
warming/climate change?
A. Carbon oxygen
B. Carbon and two oxygen
C. Carbon dioxide
D. Carbon oxide

Answers

The answer for the first question is A. Single covalent bond.

The answer for the second question is C. Carbon dioxide.

Answer:

Question 1

Which type of bond describes the coming  together and sharing of two unpaired outer  electrons, one from each atom?

A. Single covalent bond.

Definition of single covalent bond:

A single covalent bond is when only one pair of electrons is shared between atoms.

Question 2

What is the name of this molecule (CO2) that  forms by burning of fuels and is one of the  gases that contributes to global  warming/climate change?

C. Carbon dioxide.

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