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3 years ago

How do we turn petroleum into energy we use?

1 answer:

7 0

You don't "turn" it into energy; petroleum HAS stored energy (chemical energy).However, you can turn it into ANOTHER TYPE OF ENERGY; usually this is done by burning the petroleum, and using it to drive machinery.

Since burning fuels is wasteful (the efficiency is limited, in theory, to the Carnot efficiency of a heat engine), other options are being explored, such as chemical reactions in a fuel cell. But such technology is not yet used on a large scale.

You might be interested in

Explain why crushed garlic has more flavor when put in food than a whole clove of garlic.

Zigmanuir [339]

A crushed garlic will have a lot of flavor when placed in food due to the surface area that is in contact with the food. When we have a large piece of garlic, only the external part touches the food and its full capacity is not used. When we reduce the size of the year by crushing the internal parts that were not in contact with the food, now they will be, in addition, liquids are also released due to the pressure exerted on the garlic and these liquids mix more easily with the food and they give it more flavor. For better understanding we can see the following figure:

Simply to understand it, in the figure, there is a clove of whole garlic represented by the rectangle that will have a height of 3 and a width of 1, the units do not matter in this case. The area that is in contact will be equal to 8, but if we divide the garlic into three equal parts, it will have a contact area greater than 12. Therefore, the more we divide the garlic, the more area it will be in contact with the food and will give it more flavor.

5 0

1 year ago

100.00 mL of 0.15 M nitrous acid (HNO2) are titrated with a 0.15 M NaOH solution. (a) Calculate the pH for the initial solution.

wolverine [178]

Answer:

a. pH = 2.04

b. pH = 3.85

c. pH = 8.06

d. pH = 11.56

Explanation:

The nitrous acid is a weak acid (Ka = 5.6x10⁻⁴) that reacts with NaOH as follows:

HNO₂ + NaOH → NaNO₂(aq) + H₂O(l)

a. At the beginning there is just a solution of 0.12M HNO₂. As Ka is:

Ka = [H⁺] [NO₂⁻] / [HNO₂]

Where [H⁺] and [NO₂⁻] ions comes from the same equilibrium ([H⁺] = [NO₂⁻] = X):

5.6x10⁻⁴ = X² / 0.15M

8.4x10⁻⁵ = X²

X = [H⁺] = 9.165x10⁻³M

As pH = -log [H⁺]

b. At this point we have HNO₂ and NaNO₂ (The weak acid and the conjugate base), a buffer. The pH of a buffer is obtained using H-H equation:

pH = pKa + log [NaNO₂] / [HNO₂]

<em>Where pH is the pH of the buffer,</em>

<em>And [NaNO₂] [HNO₂] could be taken as the moles of each compound.</em>

<em />

The initial moles of HNO₂ are:

0.100L * (0.15mol / L) = 0.015moles

The moles of base added are:

0.0800L * (0.15mol / L) = 0.012moles

The moles of base added = Moles of NaNO₂ produced = 0.012moles.

And the moles of HNO₂ that remains are:

0.015moles - 0.012moles = 0.003moles

Replacing in H-H equation:

pH = 3.25 + log [0.012moles] / [0.003moles]

c. At equivalence point all HNO2 reacts producing NaNO₂. The volume added of NaOH must be 100mL. That means the concentration of the NaNO₂ is:

0.15M / 2 = 0.075M

The NaNO₂ is in equilibrium with water as follows:

NaNO₂(aq) + H₂O(l) ⇄ HNO₂(aq) + OH⁻(aq) + Na⁺

The equilibrium constant, kb, is:

Kb = Kw/Ka = 1x10⁻¹⁴ / 5.6x10⁻⁴ = 1.79x10⁻¹¹ = [OH⁻] [HNO₂] / [NaNO₂]

<em>Where [OH⁻] = [HNO₂] = x</em>

<em />

1.79x10⁻¹¹ = [X] [X] / [0.075M]

1.34x10⁻¹² = X²

X = 1.16x10⁻⁶M = [OH⁻]

pOH = -log [OH-] = 5.94

pH = 14-pOH

d. At this point, 5mL of NaOH are added in excess, the moles are:

5mL = 5x10⁻³L * (0.15mol / L) =7.5x10⁻⁴moles NaOH

In 100mL + 105mL = 205mL = 0.205L. [NaOH] = 7.5x10⁻⁴moles NaOH / 0.205L =

3.66x10⁻³M = [OH⁻]

pOH = 2.44

pH = 14 - pOH

5 0

2 years ago

How do the chemical properties of the halegons compare to those of the noble gases

saul85 [17]

Answer:

The halogens are extremely reactive, whilst the noble gases are mainly inert.

Only some noble gases tend to form compounds, such as xenon and krypton. However, some like helium, almost have no compounds at all. Noble gases also have octet rule shells, which causes the little reactivity associated with them. To form bonds with noble gases, a lot of energy is required to form those bonds. Halogens, on the other hand, are extremely reactive. Compounds like chlorine and fluorine must be stored carefully, as they will oxidise anything that they can find, just to get one extra electron to get an octet configuration.

Hope this helps :)

6 0

2 years ago

Read 2 more answers

One difference between mixtures and pure substances is that

defon

Answer:

The mixture is made up of different atoms and pure substance is made up of same type of atom.

The main difference is that mixture can be separated into its component by physical mean while pure substances can not be separated by physical process

Explanation:

Mixture:

The properties of the mixture are not same and contains the properties of all those component present in it.

it is a combination of one or more Pure substances and can be separated by simple physical methods.
it have varying boiling and melting point

Examples are:

mixture of salt and sand
Salt water is mixture of water and NaCl and can be separated by physical mean.

Alloys: its a mixture of different metal
Air: mixture of gases

Pure Substance:

Pure substances are those made of same type of atoms all elements and compounds are pure substances.

it can not be separated by simple physical mean

it have very constant and consistent melting and boiling point

Examples are:

Water : contain only water molecule
All elements: all elements are pure substance made of same atoms
All compounds: can not be separated by physical mean.

8 0

3 years ago

Read 2 more answers

A sample of carbon dioxide gas occuples a volume of 2.5L at standard temperature and pressure (STP). What will be the volume of

MArishka [77]

Answer:

The correct answer is 5.0 L

Explanation:

STP are defined as T=273 K and P= 1 atm

By using the ideal gas equation, we can calculate the number of moles (n) of the gas at a volume V=2.5 L:

PV= nRT

⇒n= (PV)/(RT) =(1 atm x 2,5 L)/(0.082 L.atm/K.mol x 273 K)= 0.112 mol

For a sample of argon gas, with the same number of moles (0.112 mol) but twice the temperature (T = 273 K x 2= 546 K):

V= (nRT)/P = (0.112 mol x 0.082 L.atm/K.mol x 546 K)/1 atm = 5.0 L

That is consistent with the fact that when a gas is heated, it expanses. So, if the temperature increases twice, the volume also increases twice.

5 0

3 years ago