Tag: occurrence of carbon compounds in nature

Questions Related to occurrence of carbon compounds in nature

The calorific values of wood, bituminous coal, natural gas and charcoal vary in the order:

chemistry occurrence of carbon compounds in nature calorific value study of enthalpy chemical thermodynamics

  1. wood > bituminous > natural gas > charcoal

  2. wood > bituminous coal > charcoal > natural gas

  3. natural gas > charcoal > bituminous coal > wood

  4. natural gas> bituminous coal> wood> charcoal

Show answer
Correct Option: C
Explanation:

Natural gas         $ = 43000 kJ/kg$

Charcoal             $ = 29600 kJ/kg$
Bituminous coal $ = 23250 kJ/kg$
Wood                   $  =  17400 kJ/kg$

Which of the following has the lowest calorific value?

chemistry occurrence of carbon compounds in nature calorific value study of enthalpy chemical thermodynamics

  1. $C _2H _6$

  2. $C _2H _5OH$

  3. $C _2H _4$

  4. $H _2$

Show answer
Correct Option: D
Explanation:

The calorific value is defined as the amount of heat released during complete combustion of a substance with oxygen under standard condition.

H$ _2$ has the lowest calorific value.

Calorific value gives ___________.

chemistry occurrence of carbon compounds in nature calorific value study of enthalpy chemical thermodynamics

  1. fuel efficiency

  2. amount of heat

  3. amount of light

  4. none of the above

Show answer
Correct Option: A
Explanation:

Calorific value is a measure of heating capacity of fuel. It gives the fuel efficiency.

Which one of the following has the highest calorific value?

chemistry occurrence of carbon compounds in nature calorific value study of enthalpy chemical thermodynamics

  1. Kerosene

  2. Biogas

  3. LPG

  4. Petrol

Show answer
Correct Option: C
Explanation:

The calorific value of a fuel is the quantity of heat produced by its combustion - at constant pressure and under a conditions known as " normal " of temperature and pressure (i.e. to 0oC and under a pressure of 1,013 mbar). 
The combustion of a fuel product generates water vapor. Certain techniques are used to recover the quantity of heat contained in this water vapor by condensing it. 
The Higher Calorific Value (or Gross Calorific Value - GCV) supposes that the water of combustion is entirely condensed and that the heat contained in the water vapor is recovered. 
The Lower Calorific Value (or Net Calorific Value - NCV) supposes that the products of combustion contains the water vapor. The heat contained in the water vapor is not recovered. 
LPG has a typical specific calorific value of 46.1 MJ/kg.
Calorific value of Bio gas is about 19 to 25 MJ/cubic meter, depending on the methane percentage in the biogas mix.
Heat of combustion of kerosene for lower heating value is 43.1 MJ/kg, and for higher heating value is 46.2 MJ/kg.
Petrol, calorific value of which is 45.8 MJ/kg.
Thus, LPG has highest calorific value among above.

Which of the following compounds has the highest calorific value ?

chemistry occurrence of carbon compounds in nature calorific value study of enthalpy chemical thermodynamics

  1. $CH _4$

  2. $C _2H _6$

  3. $H _2$

  4. $C _4H _{10}$

Show answer
Correct Option: C
Explanation:

Calorific value is the amount of energy produced by the complete combustion of a molecule. Amongst the given options, $H _{2}$ has the highest calorific value.

 An individual can reduce plastic pollution in the ways like :

allotropes of carbon occurrence of carbon compounds in nature polymers chemistry

  1. Use a reusable container instead of sandwich bags

  2. Bring your own to-go mug with you to the coffee shop

  3. Say no to single serving packaging, buy in bulk and share with friends instead

  4. All of these

Show answer
Correct Option: D
Explanation:
The best thing we can do to protect our waterways is try to keep as much plastic as possible out of the waste stream in the first place. There are many small ways you can have a big impact.

1. Wean yourself off disposable plastics.
Ninety percent of the plastic items in our daily lives are used once and then chucked: grocery bags, plastic wrap, disposable cutlery, straws, coffee-cup lids. Take note of how often you rely on these products and replace them with reusable versions. It only takes a few times of bringing your own bags to the store, silverware to the office, or travel mug to Starbucks before it becomes habit.
2. Stop buying water.
Each year, close to 20 billion plastic bottles are tossed in the trash. Carry a reusable bottle in your bag, and you’ll never be caught having to resort to a Poland Spring or Evian again. If you’re nervous about the quality of your local tap water, look for a model with a built-in filter.
3. Boycott microbeads.
Those little plastic scrubbers found in so many beauty products—facial scrubs, toothpaste, body washes—might look harmless, but their tiny size allows them to slip through water-treatment plants. Unfortunately, they also look just like food to some marine animals. Opt for products with natural exfoliants, like oatmeal or salt, instead.
4. Cook more.
Not only is it healthier, but making your own meals doesn’t involve takeout containers or doggy bags. For those times when you do order in or eat out, tell the establishment you don’t need any plastic cutlery or, for some serious extra credit, bring your own food-storage containers to restaurants for leftovers.
5. Purchase items secondhand.
New toys and electronic gadgets, especially, come with all kinds of plastic packaging—from those frustrating hard-to-crack shells to twisty ties. Search the shelves of thrift stores, neighborhood garage sales, or online postings for items that are just as good when previously used. 
6. Recycle (duh).
It seems obvious, but we’re not doing a great job of it. For example, less than 14 percent of plastic packaging is recycled. Check out the number on the bottom of the container. Most beverage and liquid cleaner bottles will be #1 (PET), which is commonly accepted by most curbside recycling companies. Containers marked #2 (HDPE; typically slightly heavier-duty bottles for milk, juice, and laundry detergent) and #5 (PP; plastic cutlery, yogurt and margarine tubs, ketchup bottles) are also recyclable in some areas. 
7. Support a bag tax or ban.
Urge your elected officials to follow the lead of those in San Francisco, Chicago, and close to 150 other cities and counties by introducing or supporting legislation that would make plastic-bag use less desirable.
8. Buy in bulk.
Single-serving yogurts, travel-size toiletries, tiny packages of nuts—consider the product-to-packaging ratio of items you tend to buy often and select the bigger container instead of buying several smaller ones over time.
9. Bring your own garment bag to the dry cleaner.
Invest in a zippered fabric bag and request that your cleaned items be returned in it instead of sheathed in plastic. (And while you’re at it, make sure you’re frequenting a dry cleaner that skips the perc, a toxic chemical found in some cleaning solvents.)
10. Put pressure on manufacturers.
Though we can make a difference through our own habits, corporations obviously have a much bigger footprint. If you believe a company could be smarter about its packaging, make your voice heard. 

Who influences the plastic pollution the most?

allotropes of carbon occurrence of carbon compounds in nature polymers chemistry

  1. Public

  2. Manufacturer

  3. Government

  4. All of these

Show answer
Correct Option: D
Explanation:
We all share the responsibility for environmental issues like plastic pollution. Any issue which concerns and community, has to be resolved with the co-operation of all involved; it is a "shared responsibility". Those involved are Government, Municipalities, the raw material manufacturers, the retailers, and consumers.
Because domestic waste is a mixture of materials of which plastics is only a small component, under 2% by weight, it is the responsibility of government to manage waste and a regulate its disposal.
It is the responsibility of the plastics raw material and packaging manufacturers to come up with the most cost efficient solutions, which will preserve and protect goods, minimize the use of energy and reduce the weight and volume of waste. 

Which are the ways through which each one of us may reduce plastic pollution?

allotropes of carbon occurrence of carbon compounds in nature polymers chemistry

  1. Use silverware instead of plactic utensils, keep a set at the office, bring a set on a picnic or to the beach

  2. Download your music instead of buying CDs

  3. Seek out items that are not made of plastic

  4. All of these

Show answer
Correct Option: D
Explanation:
The best thing we can do to protect our waterways is try to keep as much plastic as possible out of the waste stream in the first place. There are many small ways you can have a big impact.

1. Wean yourself off disposable plastics.
Ninety percent of the plastic items in our daily lives are used once and then chucked: grocery bags, plastic wrap, disposable cutlery, straws, coffee-cup lids. Take note of how often you rely on these products and replace them with reusable versions. It only takes a few times of bringing your own bags to the store, silverware to the office, or travel mug to Starbucks before it becomes habit.
2. Stop buying water.
Each year, close to 20 billion plastic bottles are tossed in the trash. Carry a reusable bottle in your bag, and you’ll never be caught having to resort to a Poland Spring or Evian again. If you’re nervous about the quality of your local tap water, look for a model with a built-in filter.
3. Boycott microbeads.
Those little plastic scrubbers found in so many beauty products—facial scrubs, toothpaste, body washes—might look harmless, but their tiny size allows them to slip through water-treatment plants. Unfortunately, they also look just like food to some marine animals. Opt for products with natural exfoliants, like oatmeal or salt, instead.
4. Cook more.
Not only is it healthier, but making your own meals doesn’t involve takeout containers or doggy bags. For those times when you do order in or eat out, tell the establishment you don’t need any plastic cutlery or, for some serious extra credit, bring your own food-storage containers to restaurants for leftovers.
5. Purchase items secondhand.
New toys and electronic gadgets, especially, come with all kinds of plastic packaging—from those frustrating hard-to-crack shells to twisty ties. Search the shelves of thrift stores, neighborhood garage sales, or online postings for items that are just as good when previously used. 
6. Recycle (duh).
It seems obvious, but we’re not doing a great job of it. For example, less than 14 percent of plastic packaging is recycled. Check out the number on the bottom of the container. Most beverage and liquid cleaner bottles will be #1 (PET), which is commonly accepted by most curbside recycling companies. Containers marked #2 (HDPE; typically slightly heavier-duty bottles for milk, juice, and laundry detergent) and #5 (PP; plastic cutlery, yogurt and margarine tubs, ketchup bottles) are also recyclable in some areas. 
7. Support a bag tax or ban.
Urge your elected officials to follow the lead of those in San Francisco, Chicago, and close to 150 other cities and counties by introducing or supporting legislation that would make plastic-bag use less desirable.
8. Buy in bulk.
Single-serving yogurts, travel-size toiletries, tiny packages of nuts—consider the product-to-packaging ratio of items you tend to buy often and select the bigger container instead of buying several smaller ones over time.
9. Bring your own garment bag to the dry cleaner.
Invest in a zippered fabric bag and request that your cleaned items be returned in it instead of sheathed in plastic. (And while you’re at it, make sure you’re frequenting a dry cleaner that skips the perc, a toxic chemical found in some cleaning solvents.)
10. Put pressure on manufacturers.
Though we can make a difference through our own habits, corporations obviously have a much bigger footprint. If you believe a company could be smarter about its packaging, make your voice heard. 

An infra-red spectrum shows a broad peak at $3000$ $cm^{-1}$ and a strong peak at $1710$ $cm^{-1}$. Which substance could have produced this spectrum?

allotropes of carbon occurrence of carbon compounds in nature polymers chemistry

  1. Methyl propanoate

  2. Propan-$2$-ol

  3. Propanoic acid

  4. Propanone

Show answer
Correct Option: C
Explanation:
Carboxylic acid broad peak is due -OH from 2500  to 3500 $cm^{-1}$ and strong peak due to Carbonyl bond is from 1700 to 1725 $cm^{-1}$
 So the answer is propanoic acid.

Multiple Answer question 
Instead of using plastics, these/this can be used to avoid pollution :

allotropes of carbon occurrence of carbon compounds in nature polymers chemistry

  1. Jute bags

  2. Paper bags

  3. Cloth bags

  4. Poly bags

Show answer
Correct Option: A,B,C
Explanation:

Jute bags, Paper bags, and cloth bags are all biodegradable substances and decay overtime but poly bags degrade in hundreds of years and causes pollution. Thus, they can be used in place of plastic bags.