5. How much iron at 150° C should be added to 2 kg of water at 20° C to raise the temperature of the water 50° C. (Careful!)

when heated, the valance electrons increased their speed and transferred the heat from electron to electron.   i just took the test.

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg

the ima (higher than 1m) will be greater than the ima with the height of 1m.