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some questions (1 Viewer)

ta1g

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Joined
Aug 11, 2005
Messages
30
It costs 2470 kj of energy to produce 1 kg of pure copper (II) oxide. Calculate the energy cost per mole of copper.

For the process of photosythesis calculate the mass of glucose (C6H12O6) produced if 44 g of CO2 is reacted in the leaf with excess water.


Can someone explain to me how to do these questions..simply...thanks
 

gosh

Member
Joined
May 18, 2004
Messages
162
For question 1:
<b><i>It costs 2470 kj of energy to produce 1 kg of pure copper (II) oxide. Calculate the energy cost per mole of copper.</b></i>
Write down the formula for the production of copper(II) oxide
2Cu(s) + O2(g) ---> 2CuO(s)
moles of CuO= mass/molar mass= 1000g/79.55
= 12.57
= moles of copper
.: energy cost of copper = 2470 kj/12.57 moles = 196.4885 kj/mol

For question 2:
<b><i>For the process of photosythesis calculate the mass of glucose (C6H12O6) produced if 44 g of CO2 is reacted in the leaf with excess water.</b></i>
Write down the formula for photsynthesis:
6H2O(l) + 6CO2(g) ---> C6H12O6 + 6O2(g)
moles of CO2= mass/molar mass= 44g/44 = 1
moles of glucose= 1/6 x moles of CO2 = 0.1667
.: mass of glucose= moles x molar mass= 0.1667 x 180.096
= 30.016 g

I'm not too sure if the first answer is correct but i hope the rest of it helps you
 

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