1.51 x 10²⁵atoms
Explanation:
Given parameters:
Mass of Na = 578g
Unknown:
Number of atoms = ?
Solution:
To find the number of atoms, we must first find the number of moles the given mass contains.
Number of moles = 
molar mass of Na = 23g
Number of moles = 
= 25.13moles
1 mole of a substance = 6.02 x 10²³atoms
25.13 mole of Na = 25.13 x 6.02 x 10²³atoms
This gives 1.51 x 10²⁵atoms of Na
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Avogadro's constant brainly.com/question/2746374
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If it is a really humid warm day, have you ever noticed that's when all electrical storms occur
Explanation:
Moles of N2 = 35.0g / (28g/mol) = 1.25mol
Moles of H2 = 60.0g / (2g/mol) = 30.0mol
Since 1.25mol * 3 < 30.0mol, nitrogen is limiting.
Moles of NH3 = 1.25mol * 2 = 2.50mol.
Mass of NH3 = 2.50mol * (17g/mol) = 42.5g.
30.0mol - 1.25mol * 3 = 26.25mol.
Excess mass of H2
= 26.25mol * (2g/mol) = 52.5g.
The answer is (4). You may recall the term "radiometric dating," which refers to the dating of old artifacts by measuring proportions of certain radioactive isotopes they contain and making calculations based on their estimated half-lives. Geological formations are dated in this way.
