Answer:
The number of electrons I think
Explanation:
<h3>Further explanation</h3>
Given
Atomic symbol
Required
Atomic composition
Solution
Atomic number = number of protons = number of electrons
Mass Number (A) is the sum of protons and neutrons
Number of protons and Number of Neutrons in nucleus
Number of electrons in the shell
From the picture:
protons = 3
neutrons = 4
electrons = 3
atomic number = protons = electrons = 3
mass number = protons + neutrons = 3+4 = 7
D because O3 means oxygen times 3 times it self so you add another oxygen partial it becomes O4
Mass of CO₂ = 132 g
<h3>Further explanation
</h3>
A mole is a number of particles(atoms, molecules, ions) in a substance
This refers to the atomic total of the 12 gr C-12 which is equal to 6.02.10²³, so 1 mole = 6.02.10²³ particles
Can be formulated :
N = n x No
N = number of particles
n = mol
No = 6.02.10²³ = Avogadro's number
mole also can be formulated :

moles of CO₂ = 3
mass of CO₂(MW=44.01 g/mol) :
