Which takes more energy? A) organic farming B) regular ...

[mp14]

Which takes more energy?
 
  A) organic farming
  B) regular farming
  C) synthesis of pesticides and fertilizers
  D) crop rotation
  E) All of the above are equally energy intensive.

Question 2

Calculate the amount of energy needed to raise the temperature of 25 mL ethanol (density = 0.80 g/mL) from 10.0 C to 20.0 C (c = 0.581 cal/gC) both in cal and joules.
 
  What will be an ideal response?

[coreycathey]

Answer to Question 1

C

Answer to Question 2

Density = mass/ volume; mass of ethanol = 0.80  25 = 20. g;
Heat = mass  specific heat  difference in temperature
= 20.  0.581  10 = 120 cal = 490 joules

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Thanks

[coreycathey]

Welcome