Answer:
The answer is: (a) positive; (b) negative.
Explanation:
The change in enthalpy (ΔH) of a reaction is the amount of energy absorbed or released during a chemical reaction carried out at constant pressure.
a) In an endothermic chemical reaction, heat energy is absorbed by the system from the surrounding. Therefore, the sign of enthalpy change for an endothermic process is positive, ΔH= positive.
b) In an exothermic chemical reaction, heat energy is released by the system into the surrounding. Therefore, the sign of enthalpy change for an exothermic process is negative, ΔH= negative.
The correct option is this: SPECIFIC HEAT CAPACITY IS AN INTENSIVE PROPERTY AND DOES NOT DEPEND ON SAMPLE SIZE.
Generally, all the properties of matters can be divided into two classes, these are intensive and extensive properties. Intensive properties are those properties that are not determined by the quantity of the material that is present or available. Examples of intensive properties are colour, density and specific heat capacity. For instance, whether you have a bucket of water or a cup of water, the quantity does not matter, the colour of water will always remain the same. Extensive properties in contrast, are those properties that depend on the quantity of material that is available. Examples are mass, heat capacity and volume.