A chemist requires 0.802 mol Na2CO3 for a reaction. How many grams does this correspond to?

Ok:

Explanation:

So grams = mols*MolarMass. Here, MolarMass (MM) = 105.99g which can be found using the periodic table. mols is given to be 0.802. We can then plug in to get that it corresponds to 85.0g.

organisms are more likely to be more preserved in mud than sand because mud is moist and wet, while sand is very dry.

i think it's c. i'm not sure but i think so.