Answer:
-145.2kJ
Explanation:
Enthalpy is an extensive property as its value depends on the amount of substance present in the system.
If the enthalpy for one mole of methanol = -726 kJ/mol;
The Enthalpy for 0.2 mol is given as;
Enthalpy = 0.200 * 726
Enthalpy = -145.2kJ
It would take -145.2kJ for 0.200 mol of methanol to undego the combustion reaction.
Answer:
Addition of a catalyst can speed up a reaction by providing an alternate reaction pathway that has a lower activation energy
Explanation:
A catalyst is an agent that increases the rate of a chemical reaction by providing an alternate pathway for the reaction that requires a lower activation energy. As the requirement for activation energy is less in the presence of a catalyst, there are more reactant particles becoming involved in the chemical reaction and as such there are more products formed per unit time, or there is an increase in the rate of the reaction
Example of catalyst include
1. Addition of potassium permanganate to hydrogen peroxide to aid in the rapid decomposition into water and oxygen
2. Platinum serves as a catalyst in the complete combustion of carbon monoxide into carbon dioxide.
<span>density = mass / volume
given the quotient , we have density and mass, volume can be easily calculated as:
volume = mass / p =15.5 g / 0.789 g/cm^3
=~ 20 cm^3 (dimension ally constant)</span>
