Answer:Hess's law states that the change of enthalpy in a chemical reaction (i.e. the heat of reaction at constant pressure) is independent of the pathway between the initial and final states. ... Hess's law allows the enthalpy change (ΔH) for a reaction to be calculated even when it cannot be measured directly.
Explanation:
tip
this is just a tip not the true answer but try to add the given number
The correct answer is C. As heated material gets closer to the surface, it begins to cool.
Explanation:
Convection currents involve the flow and movement of particles in gases or liquids due to changes in temperature and density. This occurs on the Earth's mantle, which is partially liquid and it is located between the core (center of Earth) and the crust composed of plates.
In this way, molten material that is near the core heats and rises as it is less dense, but once it reaches the crust it cools, and after some time it sinks again as the magma increases its density. This cycle is constant and causes the movement of the plates in the crust, that might move apart or toward other plates. According to this, the only accurate statement is "As heated material gets closer to the surface, it begins to cool".
The best answer among the choices given is option A. Chemical weathering of rocks is a source of dissolved substances in the ocean. It is a process that involves the erosion of rocks due to chemical reactions by water and substances dissolved in the water. Therefore, it most likely the source of dissolved substances.
