All categories

3 years ago

Which is the coal with the highest energy available per unit to burn: lignite, subbituminous, bituminous, or anthracite?

Chemistry

1 answer:

olya-2409 [2.1K]3 years ago

6 0

Answer:

Anthracite

Explanation:

Anthracite produce highest amount of energy than other. It contain 86-97 percent carbon. Bituminous coal contain 45-86 percent carbon.

Subbituminous cola have 35-45 percent carbon while lignite contain 25-35 percent carbon.

Coal is source of many organic materials. It is fossil fuel and form after long period decay of plants. It is formed when trees are buried under earth

about 500 million years ago. The chemical and bacterial reactions take place and plant wood converted into the peat.

Than because of high temperature and pressure inside the earth peat is converted into the coal.

Through other processes it is than used to make the fuels such as coke. coal tar and coal gas.

Coal tar is the source of many organic compounds which are separated through fractional distillation.

About 80% of coal in Pakistan is used to bake the bricks and also used in lime kilns and for domestic purpose.

You might be interested in

Scientists use scientific notation to represent very small or very large numbers because this notation increases the

Tems11 [23]

...because this notation increases the convenience in using the numbers

3 0

2 years ago

Read 2 more answers

A transformer has 90 turns in the primary coil and 9 turns in the secondary coil If the output voltage is 6 V, what is the input

Afina-wow [57]

Answer:

60 V

Explanation:

From;

Vs/Vp = Ns/Np

Where;

Vs = voltage in the secondary coil = 6V

Vp = voltage in the primary coil= ??

Ns = number of turns in the secondary coil = 9

Np= number of turns in the primary coil = 90

6/Vp = 9/90

Vp= 90 * 6/9

Vp= 60 V

6 0

2 years ago

Define significant figure. Discuss the importance of using the proper number of significant figures in measurements and calculat

anastassius [24]

Explanation:

Significant figure is the measure of how accurately something can be measured. It carries meaning contributing to its measurement resolution. It is important to use proper number of significant figures to get a precise measurement. For example, if we use a meter stick then measurements like 0.874 meters, or 0.900 meters, are good because they indicate that we can measure to the nearest millimeter. Whereas a measurement like 0.8 does not tell that a meter stick can measure to the nearest millimeter.

7 0

2 years ago

Thallium-207 decays exponentially with a half life of 4.5 minutes. if the initial amount of the isotope was 28 grams, how many g

Agata [3.3K]

An exponential decay law has the general form: A = Ao * e ^ (-kt) =>

A/Ao = e^(-kt)

Half-life time => A/Ao = 1/2, and t = 4.5 min

=> 1/2 = e^(-k*4.5) => ln(2) = 4.5k => k = ln(2) / 4.5 ≈ 0.154

Now replace the value of k, Ao = 28g and t = 7 min to find how many grams of Thalium-207 will remain:

A = Ao e ^ (-kt) = 28 g * e ^( -0.154 * 7) = 9.5 g

Answer 9.5 g.

7 0

3 years ago

How do you balance a chemical equation

Dominik [7]

There should be mass balance and the charge balance between the reactants and the products

Mass balance : total no of individual atoms of each type should be balanced before and after the reaction

Charge balance : Overall charge of the reactants should be balanced with the overall charge of the products

You can balance,

1)by just looking at it

2)by Algebraic method given above or

3)by the redox method

You need to know how to get the oxidation numbers in order to use the oxidation method

6 0

2 years ago