SiO2 + 3C -> SiC +2CO If 100 grams of C are to react completely, how many grams of SiO2 are needed?

Which part of earth’s surface receives the most direct rays from the sun? a) equator b) ocean c) poles d) mountains

When balancing a chemical equation:

As air becomes more dense, (select all that apply) o. air weighs less o. gas molecules are closer together o. air is colder o. air weighs more o. gas molecules are further apart o. air is hotter