How much heat transfer (in kilocalories) is required to thaw a 0.450-kg package of frozen vegetables originally at 0ºc if their heat of fusion is the same as that of water?

To thaw a product requires it to undergo the process of being subjected to latent heat of fusion. In this process, there is no change in temperature however there is a change of phase from solid to liquid. What is being thawed here actually is the frozen ice into liquid water which is in the vegetables.

From the references, the latent heat of fusion of water is:

Δ H = 333.55 kJ / kg

Therefore the amount of heat required to thaw the frozen vegetable is:

Heat required = Δ H * m

Heat required = (333.55 kJ / kg) (0.450 kg)

Heat required = 150.10 kJ

In 1 kcal there is 4.184 kJ, therefore:

Heat required = 150.10 kJ (1 kcal / 4.184 kJ)

Heat required = 35.87 kcal

answer: option c. i.e. electric current flowing “downhill” from the negative electrode to the positive electrode in a battery

explanation:

the water analogy to the circuits define the pipes (water flows) to the electric current. now, we know that the electric current flows from the positive terminal to the circuit (as shown in the diagram attached).

hence, option c is the correct answer.

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force