Answer:
Ventilators are provided in the rooms at the top of the roofs because if the air inside the room gets hot, the hot air rises up and flows through these ventilators and thus cool air remains at bottom. Thus ventilators maintain conventional currents to keep the air fresh in the room.
Explanation:
Can vary. Carbon is used quite commonly, and extracts metal oxides, works with zinc, iron, tin, lead and copper.
Answer:
Explanation:
You just have to see the REACTANTS and PRODUCTS and look how much molecules are there and accordingly put numbers.
Eg:4Fe+3O2--------->2Fe2O3
