Answer is ₂₀⁴²Ca.<span>
In AZX notation
A<span> - Represents the </span>mass number of atom.
Mass number = number of
protons + number of neutrons.
<span> It is shown at
the </span>above of the left side<span> of the
atom.</span>
<span> Here it is </span>42.
<span> </span>Z - Represents the atomic number.<span>
Atomic number = number of protons.
</span><span>It is shown at the</span> bottom line of the left side of the atom.<span>
</span>Here it is 20.<span>
X - </span>Represents the symbol of the atom.<span>
<span> </span></span>Here</span> X is Ca.<span>
</span>
Answer:
1. BF3 This is a trigonal planar molecule; the electron density is drawn into a cloud that circles the Boron, this is made nonpolar by the geometrically equivalent structure of the surrounding electronegative Fluorines.
2. H2O The 2 lone pairs of e- of Oxygen makes the O partially negative, the H’s, partially positive. Polar.
3. NF3 Lone pair on Nitrogen overwhelmed by the 3 incredibly electronegative Fluorines. Polar
4. CH3Br The “Soft Ion” of Bromine is negative; it is electronegative. Polar.
5. SO2 the lone pairs of Oxygen, at approximately 119°-120° angles to one another will form a reasonance structure; there will be more lone pairs about the Oxygen than the Sulfur; the Sulfur will be partially positive compared to the oxygens. Polar.
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
Learn more about moles here:
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Answer:
Humus, which ranges in colour from brown to black, consists of about 60 percent carbon, 6 percent nitrogen, and smaller amounts of phosphorus and sulfur. As humus decomposes, its components are changed into forms usable by plants.
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