To find the number of moles from a mass given, simply look to the formula n (moles) = m (mass, g) / MM (molar mass).
Mass was given, 36.04
Molar mass is the total atomic mass of all the atoms present. Water is H20, so that means 2 hydrogen and 1 oxygen. The atomic mass of hydrogen is 1 and atomic mass of oxygen is 16. Therefore MM= 1 + 1 + 16= 18.
Plug that value in and the full equation is
n = 36.04/18
n = 2.002 moles
= 2 moles
They both have two electron shells
<h3>Further explanation</h3>
The period 2 element lies in the second row of the periodic system.
Consists of the elements: lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, and neon
atomic number : 3
electron configuration : [He] 2s¹
atomic number = number of proton=number of electron(in neutral atom)
So Li have 3 protons and 3 electrons
Because it fills the 2s orbital it has 2 shells
atomic number : 8
electron configuration : [He] 2s²2p⁴
So O have 8 protons and 8 electrons
Because it fills the 2s and 2p orbital it has 2 shells
So Lithium (Li) and Oxygen (O) are both have two electron shells
I would think that the answer would be three
Because of the prefix tri- in "tigonal"
Tri- means 3, as in tricycle or triangle
So, it would make sense for the answer to be 3
