Answer:
By counting the number of atomic number
Answer is: there are 3.011·10²³ atoms of calcium.
n(Ca) = 0.50 mol; amount of substance(calcium).
Na = 6.022·10²³ 1/mol; Avogadro's constant or number.
N(Ca) = n(Ca) · Na.
N(Ca) = 0.50 mol · 6.022·10²³ 1/mol.
N(Ca) = 3.011·10²³; number of calcium atoms.
The mole is an SI unit which measures the number of particles in substance. One mole is equal to <span><span>6.022</span></span>·<span><span><span>10</span></span></span>²³<span> atoms.</span>
I would say you are correct so b 4.6
D. in a refrigerator in a small container
Concept:
When an atom has incomplete number of electron in its outermost orbit then it has great tendency to react with another atom which satisfies their octate either by sharing or by transferring their electrons. The involved electrons are called valence electrons.
In case of electrovalent compound, the valance electron complete their octate by transferring their valence electrons while in the covalent compound, they complete their octate by the sharing of their valence electrons.
Hence, the valence electron of the atom is involved in chemical bonding with other atoms.