
1 g of dry green algae absorb 4.7$ \times {10^{ - 3}}$ moles of $C{O_2}$ per hour by photosynthesis. If the fixed carbon atom after photosynthesis is stored in the form of starch (${C_6}{H_{10}}{O_5}$) Cal. How much time will it take algae to double its own weight ?
Answer
482.7k+ views
Hint: In the question, the rate of absorption of carbon dioxide by the algae is provided. And even the amount required is also given. We need to find the moles of carbon needed to fix and then by dividing the moles by absorption rate, we will get the time taken by the green algae.
Complete Solution :
Let us first write what is given and what we need to find out and then move step by step to get an answer.
Given :
Mass of dry green algae = 1 g
Absorption rate of algae = 4.7$ \times {10^{ - 3}}$ moles of $C{O_2}$ per hour
To find :
Time taken by algae to double its own weight
So, we need to find the time taken by algae to get 1 g weight.
The starch has molecular formula - ${C_6}{H_{10}}{O_5}$
As the Carbon dioxide is fixed in the form of starch. So, we need to find out the time taken for the formation of 1 g of starch.
Molar mass of starch = 162 g
The reaction is -
$C{O_2} \to {({C_6}{H_{10}}{O_5})_n}$
We know that moles of Carbon in $C{O_2}$ = 6n $ \times $ moles of Carbon in ${({C_6}{H_{10}}{O_5})_n}$ = 6 $ \times \dfrac{1}{{n(162)}}$
So, moles of carbon dioxide required = $\dfrac{6}{{162}}$
moles of carbon dioxide required = 0.037 moles
Rate of absorption = 4.7$ \times {10^{ - 3}}$ moles/ hr
Time (hr) = $\dfrac{{0.037}}{{4.7 \times {{10}^{ - 3}}}}$
Time (hr) = 7.88 hr
Note: It must be noted that green plants make their own food by the process of photosynthesis. In this process, green plants take up carbon dioxide and water from the atmosphere and in the presence of sunlight, convert it into starch. This starch is the stored food.
Complete Solution :
Let us first write what is given and what we need to find out and then move step by step to get an answer.
Given :
Mass of dry green algae = 1 g
Absorption rate of algae = 4.7$ \times {10^{ - 3}}$ moles of $C{O_2}$ per hour
To find :
Time taken by algae to double its own weight
So, we need to find the time taken by algae to get 1 g weight.
The starch has molecular formula - ${C_6}{H_{10}}{O_5}$
As the Carbon dioxide is fixed in the form of starch. So, we need to find out the time taken for the formation of 1 g of starch.
Molar mass of starch = 162 g
The reaction is -
$C{O_2} \to {({C_6}{H_{10}}{O_5})_n}$
We know that moles of Carbon in $C{O_2}$ = 6n $ \times $ moles of Carbon in ${({C_6}{H_{10}}{O_5})_n}$ = 6 $ \times \dfrac{1}{{n(162)}}$
So, moles of carbon dioxide required = $\dfrac{6}{{162}}$
moles of carbon dioxide required = 0.037 moles
Rate of absorption = 4.7$ \times {10^{ - 3}}$ moles/ hr
Time (hr) = $\dfrac{{0.037}}{{4.7 \times {{10}^{ - 3}}}}$
Time (hr) = 7.88 hr
Note: It must be noted that green plants make their own food by the process of photosynthesis. In this process, green plants take up carbon dioxide and water from the atmosphere and in the presence of sunlight, convert it into starch. This starch is the stored food.
Recently Updated Pages
Master Class 9 General Knowledge: Engaging Questions & Answers for Success

Earth rotates from West to east ATrue BFalse class 6 social science CBSE

The easternmost longitude of India is A 97circ 25E class 6 social science CBSE

Write the given sentence in the passive voice Ann cant class 6 CBSE

Convert 1 foot into meters A030 meter B03048 meter-class-6-maths-CBSE

What is the LCM of 30 and 40 class 6 maths CBSE

Trending doubts
Which one is a true fish A Jellyfish B Starfish C Dogfish class 11 biology CBSE

What is the difference between superposition and e class 11 physics CBSE

State and prove Bernoullis theorem class 11 physics CBSE

1 ton equals to A 100 kg B 1000 kg C 10 kg D 10000 class 11 physics CBSE

State the laws of reflection of light

One Metric ton is equal to kg A 10000 B 1000 C 100 class 11 physics CBSE
