can anyone answer a simple question regarding heat capacity?

Question

here it is: 1 kg of water is heated together with 1 kg of iron. which of these two would require a greater amount of heat?

correct me if i'm wrong. this is what i think: water would require a greater heat because it has a greater heat capacity.

Answer 1

Specific heat of water is 4200J/Kg-K and specific heat of iron is 444J/Kg-K. You are right, since water has greater specific heat capacity, it would require greater heat for one degree rise of temperature. But you need to understand one aspect. It does not matter whether they are together or separate, the heat required by water and iron are different. All that makes the difference is that, if they are heated together, then they absorb the heat energy in such a way that, their temperatures would rise at the same rate. This obviously indicates that water and iron would absorb energy at different rates.

Answer 2

Water would require a greater heat because 1 kg of water has a greater heat capacity than 1kg of iron.

If you are not mentioning the mass, then the answer is not complete.

The amount of heat required is proportional to the mass also.

You can also say as follows.

Water would require a greater heat because it has a greater heat capacity than the same mass of iron.

Answer 3

If you heat 1 Kg of water taken in a vessel made of 1 Kg iron, then water needs more heat whereas if you want to heat 1 Kg of iron dipped in 1 Kg of water ( obviuosly in some container) then iron needs more heat . This is because heat has to be transfered from iron to steel or viceversa.

Answer 4

You are correct. Water has the highest specific heat of all substances and hence water would need more heat than iron in this case.

Answer 5

C3H8(gas) + 5O2(gas) = 3CO2(gas) + 4H2O(g) (water vapour) (liquid (l) when condensed). Heat (exothermic reaction), and light (flames) is are also produced. They don't really affect the problem except that, liquid fuels will not burn. They have to be in gaseous form in order to combust with oxygen, which is a gas above -183°C. CO2 is a gas at -78°C and above. (We also have (aq) as in HCl(aq)...This indicates an aqueous solution of HCl gas (Hydrochloric acid) and, (s) solid substance). Some subscripts and superscripts ('little' numbers) are difficult to produce in 'Answers'. ₀⁰₁¹₂²₃³₄⁴₅⁵₆⁶₇⁷₈⁸₉⁹. Some, as can be seen, are virtually unreadable.