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    Hi, so this is a calculation question and I just can't get the right answer!

    'The combined store of oxygen in a 450 kg Weddell seal is about 30 litres. The average rate of consumption in tissues is about 250cm^3 kg-1 hour -1'

    Calculate the time you would expect a 450kg seal to be able to remain under water, respiring aerobically.'

    (the answer is 16 minutes)

    Thanks in advance!
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    first find the rate of oxygen conversion per hour for the seal: 450Kg x 250cm^3= 112500cm^3 per hour.Find the volume of oxygen stored in the seal (1l=1000cm^3)=30 x 1000= 30000 cm^3so we know our seal consumes 112500 cm^3 of oxygen per hour which is 1875 cm^3 per minute. Divide 30000 by 1875 to give you the minutes it takes for the seal to consume its oxygen supply=16 minutes
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    (Original post by tremen222)
    first find the rate of oxygen conversion per hour for the seal: 450Kg x 250cm^3= 112500cm^3 per hour.Find the volume of oxygen stored in the seal (1l=1000cm^3)=30 x 1000= 30000 cm^3so we know our seal consumes 112500 cm^3 of oxygen per hour which is 1875 cm^3 per minute. Divide 30000 by 1875 to give you the minutes it takes for the seal to consume its oxygen supply=16 minutes
    Thank you!
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    Okay so...

    1 hour = 250cm3 (per 1kg)
    1 hour therefore = 0.25 litres

    Therefore if 0.25 = 1kg
    450kg = 112.5 litres.

    SO 112.5/60 = 1.875 litres oxygen used per min.

    1.875 = 1 min
    It has 30 litres of oxygen

    SO 30/1.875 = 16 minutes!

    Oops! Just realised someone had already done it!! Sorry!
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    (Original post by GCSEStudent903)
    Okay so...

    1 hour = 250cm3 (per 1kg)
    1 hour therefore = 0.25 litres

    Therefore if 0.25 = 1kg
    450kg = 112.5 litres.

    SO 112.5/60 = 1.875 litres oxygen used per min.

    1.875 = 1 min
    It has 30 litres of oxygen

    SO 30/1.875 = 16 minutes!

    Oops! Just realised someone had already done it!! Sorry!
    Na I appreciate it thanks!
 
 
 
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