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Answer:

The amount of energy released from the combustion of 2 moles of methae is 1,605.08 kJ/mol

Explanation:

The chemical reaction of the combustion of methane is given as follows;

CH₄ (g) + 2O₂ (g) → CO₂ (g) + 2H₂O (g)

Hence, 1 mole of methane combines with 2 moles of oxygen gas to form 1 mole of carbon dioxide and 2 moles of water vapor

Where:

CH₄ (g): Hf = -74.6 kJ/mol

CO₂ (g): Hf = -393.5 kJ/mol

H₂O (g): Hf = -241.82 kJ/mol

Therefore, the combustion of 1 mole of methane releases;

-393.5 kJ/mol × 1 + 241.82 kJ/mol × 2 + 74.6 kJ/mol = -802.54 kJ/mol

Hence the combustion of 2 moles of methae will rellease;

2 × -802.54 kJ/mol or 1,605.08 kJ/mol.

Answer: answer is C

Explanation:

Just took the test

Answer:

Salt bridge

Explanation:

Salt bridge is used in an electrolytic cell to transfer electrons from the anode to the cathode.

Salt bridge are used because they do not interfere with the constituents of the cell I.e the anode (+very electrode) and cathode(-ve electrode).

Examples of salt bridges are AgNO₃, KCl etc.

Salt bridge can be described as a tool used to link the oxidation half cell and reduction half cell in an electrolytic set-up or galvanic cell.

Answer:

28c

Explanation:

Answer:

A substance that tends to bring about oxidation by being reduced and gaining electrons

Explanation:

Answer:

An oxidizing agent is a substance that takes negatively charged electrons "away" from a substance or object; usually taking these electrons for itself it can also transport the electrons from an object and "give" them to another substance or object. The object that has been oxidized will then have a positive charge after losing the negative electrons and the substance receiving the electrons will become negative.

Explanation:

Examples include halogens, potassium nitrate, and nitric acid.

Answer:

4.97 atm

Explanation:

P2=V1P1/V2

I know this is correct because P and V at constant T have an inverse relationship.

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Answer:

I believe the answer would be A

Answer:

Frequency = Velocity / Wavelength

or

f = v / λ

Answer:

Nvr XD

Explanation:

Answer:

the world may never know

Explanation:

Answer: -18

Explanation:

Facts

What is the value for ΔG at 500 K if ΔH= 27 kJ/mol and ΔS = 0.09 kJ/(mol⋅K)?

Explanation: ΔG= -18 kJ/mol

Answer:

Matter is anything that is made up of atoms. Whether its a computer, a drink, a suitcase, a telephone, whatever.

If it has mass, if it occupies space, and if it has volume, then it is matter.

Also, matter comes in the form of solids, liquids, and gasses.

In this case, the telephone is a solid.

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Answer:

Matter is anything that is made up of atoms.

Explanation:

If it has mass, occupies space, and has volume, then it is matter. Also, matter comes in the form of solids, liquids, and gasses. The telephone is a solid.

Answer:

Surface area

Explanation:

The rate of a chemical reaction is increased when the surface area of a solid reactant is increased. This can be done by cutting the substance into small pieces, or by grinding it into a powder. If the surface area of a reactant is increased, it implies more particles are exposed to the other reactant.

When a seltzer tablet is ground into powder, the idea is to expose more of its surface to the other reactant. Since rate reaction depends on effective collision between reactants, more exposed particles implies a greater degree of collision between reactants and a faster rate of reaction.

Answer:

the answer is the second option got it right so do worry

Explanation:

hope this helps

Explanation:

I don't know how to explain

Answer:

a new substance is produced

Explanation:

i just took my test and got this question right

The best evidence that a chemical reaction occurs when coal burns is a new substance is produced. The correct option is A.

Coal is a carbon containing fossil fuel, which is formed when the organic matter is decomposed inside the earth with heat and pressure by the earth crust. It is the most used fossil fuel.

Carbon dioxide is a gas produce when these fossils fuel burned. It is a green house gas and increase the warmth of the earth when produced. It is taken by plants to make their food.

When coal burns, it produces carbon dioxide which is a gas and coal is a solid, so here the chemical reaction is happening which is producing a new substance.

Thus, the correct option is A. A new substance is produced.

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Answer:

458.7 mmHg

Explanation:

Step 1:

Data obtained from the question. This includes:

Initial volume (V1) = 70L

Initial pressure (P1) = 600 mmHg

Initial temperature (T1) = 20°C

Final temperature (T2) = 15°C

Final volume (V2) = 90L

Final pressure (P2) =...?

Step 2:

Conversion of celsius temperature to Kelvin temperature.

This is illustrated below:

T(K) = T (°C) + 273

Initial temperature (T1) = 20°C

Initial temperature (T1) = 20°C + 273 = 293K

Final temperature (T2) = 15°C

Final temperature (T2) = 15°C + 273 = 288K

Step 3:

Determination of the new pressure of the gas.

The new pressure of the gas can be obtained by using the general gas equation as shown below:

P1V1/T1 = P2V2/T2

600 x 70/293 = P2 x 90/288

Cross multiply to express in linear form

P2 x 90 x 293 = 600 x 70 x 288

Divide both side by 90 x 293

P2 = (600 x 70 x 288) / (90 x 293)

P2 = 458.7 mmHg

Therefore, the new pressure of the gas is 458.7 mmHg

Answer:

l

Explanation:

Answer:

B

Explanation:

Answer:

Al(OH)3 + HNO3 = Al(NO3)3 + H2O - Chemical Equation Balancer.

Explanation:

Answer:

63/16

Explanation:

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Answer:

63/16

Explanation:

this for delta math?

the answer is z = 47.214

Answer:

z = 47.214

Hope this helped

Answer:

.2 M

Explanation:

grams/molar mass=ans./volume(L)=molarity

5.6/56=ans./.500=.2 M

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Answer:

Pipette and Burettes

Explanation:

The two instruments that can be used for  

a) Pipette – It is used to dispense measured volume of any liquid into any other equipment. Pipette works on the concept of creating a partial vacuum to take in the liquid and then release the volume  to dispense the  liquid.

b) Burettes – It has a stopcock that regulate the release of liquid. It is larger than the pipette and works as a graduated cylinder.

Considering the two acids and bases involved, the reverse reaction is favored.

The term reversible reaction refers to a reaction that can go either forward or backwards depending on the conditions of the reaction.

We must recall that acetic acid is a weak acid hence the equilibrium position would always lie towards the left hand side of the equation. Hence considering the two acids and bases involved, the reverse reaction is favored.

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Answer:manufacture

Explanation:

The pollution can be controlled with the help of reducing the need for the manufactured good and transportation.

A pollution can be given as the presence of the harmful substances in the environment. The harmful substances known as pollutants deteriorate the quality of the environment and effect the health of living organism as well.

The pollution in air has been contributed with the increased need of the manufactured goods and transportation, and thereby the reduction will be found to reduce the pollution too.

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Answer:

Yes very much so, especially gases

Explanation:

Solubility of gases decrease with increasing pressure. Be familiar with Henry's Law.

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Answer:

Yes, it does.

The balanced equation based on half-reactions is 2Cu + 8HNO3 + 6H+ -> 2Cu(NO3)2 + 2NO + 4H2O.

To complete the balanced equation for the given reaction Cu + HNO3 -> Cu(NO3)2 + NO + H2O using half-reactions, we need to break down the overall reaction into separate oxidation and reduction half-reactions.

1. Oxidation Half-Reaction:

Cu -> Cu2+ + 2e-

In this step, copper (Cu) is oxidized, losing two electrons to form copper(II) ions (Cu2+).

2. Reduction Half-Reaction:

HNO3 + 3H+ + 2e- -> NO + 2H2O

In this step, nitric acid (HNO3) is reduced, gaining two electrons to form nitric oxide (NO) and water (H2O).

Now, to balance the half-reactions, we need to make sure that the number of electrons gained in the reduction half-reaction is equal to the number of electrons lost in the oxidation half-reaction. In this case, we can achieve this by multiplying the oxidation half-reaction by two.

Balanced Half-Reactions:

Oxidation: 2Cu -> 2Cu2+ + 4e-

Reduction: HNO3 + 3H+ + 2e- -> NO + 2H2O

Finally, we can combine the balanced half-reactions to obtain the balanced equation for the overall reaction:

2Cu + 8HNO3 + 6H+ -> 2Cu(NO3)2 + 2NO + 4H2O

Therefore, the balanced equation based on half-reactions is 2Cu + 8HNO3 + 6H+ -> 2Cu(NO3)2 + 2NO + 4H2O.

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Answer:

HCl is a strong acid, it dissociates 100% (I.e. completely): [HCl]F = 0.020 M = [H3O+] So, pH = - log [H3O+] = -log [HCl]F = -log(. 020)=1.70 Voila!

Answer:Releasing insulin to decrease blood sugar and releasing glucagon to increase blood sugar

Explanation: homoestasis is the process by which the body keep it's internal environment constant, regardless of change in the external environment. The human body has a normal range in which it's system operates and it uses homoestasis to keep these at constant.

Homeostasis could be positive or negative. It usually involves a sensor which detects the changes in the body and passes the information to the control center, a control center which receive information from the sensor and sends signals to the effectors and the effector which acts on the information sent by the control center to effect normalcy.

In this case, when a person eats food,he gets glucose. Blood sugar most be kept at constant so the endocrine system release the hormone insulin. Insulin helps to convert glucose to glycogen, which is the form it can be stored in the liver

When the blood sugar levels is low, the brain which is the control center causes glucagon to be released . This hormone converts glycogen to glucose

Answer:

Answer:Releasing insulin to decrease blood sugar and releasing glucagon to increase blood sugar

Explanation: