Tag: carbon cycling

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Questions Related to carbon cycling

Multiple choice biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

Which of the following conditions regarding a chemical process ensures its spontaneity at all temperature ? 

  1. $\Delta A > 0, \Delta S < 0$
  2. $\Delta H < 0, \Delta S > 0$
  3. $\Delta H < 0, \Delta S < 0$
  4. $\Delta H > 0, \Delta S > 0$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

For a process to be spontaneous at all temperatures, the Gibbs free energy change (delta G = delta H - T*delta S) must be negative. This occurs when delta H is negative (exothermic) and delta S is positive (increase in entropy).

Multiple choice biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

__________ has the lowest percentage of carbon.

  1. Lignite

  2. Bituminous

  3. Anthracite

  4. Peat
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Peat found in the lowest depth of earth considering the other forms of coal.It also has the lowest percentage of carbon as compared to other forms.In other words, we can say that they are the youngest fossils.

It contains about 27-40% of carbon content.
So the answer is $D$.

Multiple choice biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

Which form of coal has the highest carbon content in it?

  1. Lignite

  2. Sub-bituminous

  3. Bituminous

  4. Anthracite
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The order of carbon content is as follows:

Lignite < sub-bituminous < bituminous < anthracite 
Hence, anthracite has highest carbon content. It is a hard, compact variety of coal that has a good lustre.

Multiple choice biology coal, petroleum and petrochemicals carbon cycling mineral coal carbon cycle coal and its products

Peat is the first stage product of coal consisting of $60$% carbon.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Peat is a fuel consisting of spongy material formed by the partial decomposition of organic matter in wetlands such as swamps, bogs, and moors. Peat contains tree cellulose, more than $75$% moisture and less than $60$% carbon.