Release less energy than it uses
Mass number is the total number of protons and neutrons in the nucleus
Answer: The fourth material that is added to the blast furnace is HOT AIR which provides OXYGEN for used for combustion of carbon (Coke).
Explanation:
Iron is the second most abundant metal found in the earth's crust after aluminium. It is not found in the free metallic state but are extracted from rocks which are rich in iron that contains other materials. These are known are iron ores and the most common iron ores are haematite ( Fe2O3).
Iron can be extracted from its ore with the used of blast furnace. The materials used for extraction of iron includes:
--> Coke
--> haematite( iron ore)
--> limestone and
--> Hot air.
The iron ore is first roasted in air so that iron(III)oxide is produced. The iron(III)oxide is then mixed with coke and limestone and heated to a very high temperature. Hot air is introduced into it from the bottom of the furnace. The coke is oxidizes the the oxygen in the hot air blast to liberate carbondioxide.
Answer:
Option 3. The catalyst does not affect the enthalpy change (
) of a reaction.
Explanation:
As its name suggests, the enthalpy change of a reaction () is the difference between the enthalpy of the products and the reactants.
On the other hand, a catalyst speeds up a reaction because it provides an alternative reaction pathway from the reactants to the products.
In effect, a catalyst reduces the activation energy of the reaction in both directions. The reactants and products of the reaction won't change. As a result, the difference in their enthalpies won't change, either. That's the same as saying that the enthalpy change of the reaction would stay the same.
Refer to an energy profile diagram. Enthalpy change of the reaction measures the difference between the two horizontal sections. Indeed, the catalyst lowered the height of the peak. However, that did not change the height of each horizontal section or the difference between them. Hence, the enthalpy change of the reaction stayed the same.
