Answer:
M = 16.8 M
Explanation:
<u>Data:</u> HNO3
moles = 12.6 moles
solution volume = 0.75 L
Molarity is represented by the letter M and is defined as the amount of solute expressed in moles per liter of solution.

The data is replaced in the given equation:

The mass of magnesium, which has a density of 1.74 g/cm is 504.6 g.
<h3>What is mass?</h3>
Mass is the quantity of matter. Mass can be calculated by multiplying density by volume.
Magnesium is a chemical element with the atomic number 12. It is needed in the body in trace amounts. It can cause malnutrition in the body.
Mass = Density x volume
We know the density and the volume of magnesium.
Density = 1.74
Volume = 290
Density x volume
Putting the value in the equation
1.74 x 290 = 504.6 g
Thus, the mass of magnesium is 504.6 g.
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The number of C atoms in 0.524 moles of C is 3.15 atoms.
The number of
molecules in 9.87 moles
is 59.43 molecules.
The moles of Fe in 1.40 x
atoms of Fe is 0.23 x 
The moles of
in 2.30x
molecules of
is 3.81.
<h3>What are moles?</h3>
A mole is defined as 6.02214076 ×
of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
A. The number of C atoms in 0.524 mole of C:
6.02214076 ×
x 0.524 mole
3.155601758 atoms =3.155 atoms
B. The number of
molecules in 9.87 moles of
:
6.02214076 ×
x 9.87
59.4385293 molecules= 59.43 molecules
C. The moles of Fe in 1.40 x
atoms of Fe:
1.40 x
÷ 6.02214076 × 
0.2324754694 x
moles.
0.23 x
moles.
D. The moles of
in 2.30x
molecules of
:
2.30x
÷ 6.02214076 × 
3.819239854 moles=3.81 moles
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Molality is defined as 1 mole of a solute in 1 kg of solvent.
Molality=

Number of moles of solute, n=

Given mass of the nitrobenzene=0.2 g
Molar mass of the substance= 123.06 g mol⁻¹
Number of moles of nitrobenzene,

Number of moles of nitrobenzene, n= 0.0016 mol
Mass of 10.9 g of naphthalene in kg=0.0109

Molality= 0.146 m
Answer:
28
Explanation:
electron = atomic number - charge(if the charge is positive and addition if the charge is negative)
electron = 30 - 2
electron = 28