Investigate: Note the empty jars on the shelf that can be filled by using the slider. Set the amount to 2.000 moles of carbon (mol C), then press Start. Each jar holds exactly one mole of carbon. Your goal is to determine the mass in grams of two moles of carbon. Before you can find the mass, what do you need to know

The molar mass of carbon

Explanation:

Before the mass (in grams) of two moles of carbon can be determined, the molar mass of the element would be needed.

This is because the number of mole of an element is the ratio of its mass and the molar mass. That is,

number of mole = mass/molar mass

Hence, the mass of elements can be obtained by making it the subject of the formular;

mass = number of mole x molar mass

Therefore, the molar mass of carbon would be needed before the mass of 2 moles of the element can be determined.

the answers would be

the first one and the second one

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

if you need further assistance, let me know: )

~ trueboss72