They all just formed on top of each other like sedimentary rocks
Scientists developed symbols and gave the elements numbers to help organize the elements by their chemical properties. The periodic table helps identify the underlying chemical and physical traits of the elements.
Gold is a chemical element with symbol Au (from Latin: aurum) and atomic number 79, making it one of the higher atomic number elements that occur naturally. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal.
Answer:
cornea, pupil, lens, vitreous humor
First, you need to find:
One mole of

is equivalent to how many grams?
Well, for this you have to look up the periodic table. According to the periodic table:
The atomic mass of Calcium Ca = 40.078 g (See in group 2)
The atomic mass of <span>Chlorine Cl = 35.45 g (See in group 17)
</span>
As there are two atoms of Chlorine present in

, therefore, the atomic mass of

would be:
Atomic mass of

= Atomic mass of Ca + 2 * Atomic mass of Cl
Atomic mass of

= 40.078 + 2 * 35.45 = 110.978 g
Now,
110.978 g of

= 1 mole.
75.9 g of

=

= 0.6839 moles.
Hence,
The total number of moles in 75.9g of

= 0.6839 moles
According to <span>Avogadro's number,
1 mole = 1 * </span>

molecules
0.6839 moles = 0.6839 *

molecules =

molecules
Ans: Number of molecules in 75.9g of
=
molecules
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