How did scientists calculate the most exact value for the mole? through the charge of an electron and Faraday’s constant
through counting the atoms in a sample of carbon-12 under a microscope
through x-ray diffraction of silicon atoms

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

the answer is c i believe

answer:

the reaction is type of combination reaction.

explanation:

on the product side, there are 2 molecules of bonded to fe   which means one atom of fe are combined two molecules of . so, balanced chemical equation becomes :

this reaction follows the reaction type of combination reaction. a combination reaction is defined as chemical reaction in which reactants combines together to form a single product.

ca has a crystalline lattice with positive ions (since it is a metal, metals are positively charged) and electrons flow freely in its structure since the ca atoms have a large nuclear radius so the electrons are not tightly held, therefore the electrons can flow freely since they are not being highly attracted by the nucleus. moreover, one of the properties of metals are that they are conductors of electricity, thus proving ca is the element.