which requires more energy, increasing the temperature of a 1kg block of aluminum by 20 degrees celsius or raising the temperature of 500g of water by 5 degrees celsius

Answer 1

Look up the specific heat of Al and H2O. Then q = mass Al x sp. h. Al x (delta T). and

q = mass H2O x sp. h. water x (delta T).
Watch the units. Al is in Kg and H2O is in grams. Make sure the specific heat is in the right units.