8.98
×
N
A
cobalt atoms
Explanation:
N
A
,
Avogadro's number
specifies
6.0221
×
10
23
individual particles. It is simply another collective number like a dozen, or a score, or a gross.
N
A
has the property that
6.0221
×
10
23
individual cobalt atoms has a mass of
58.93
⋅
g
. How did I know that? Did I have it memorized?
So the quantity is
≈
54
×
10
23
cobalt atoms.
Answer:
As metals are giant lattice structures, the number of electrostatic forces to be broken is extremely large, and so metals have high melting and boiling points. This means that the melting point and boiling point of metals are more similar to those for ionic compounds than for covalent substances.
Explanation:
No of moles of MgCl2 = weight of MgCl2 / Molecular weight of MgCl2
Weight of MgCl2 =moles of MgCl2 x molecular mass of MgCl2
= 8.90 x 95=845.5 gm
Answer:
Energy levels tell us how many <u>electrons </u>there are in an atom.
Hope this helps!
The element symbol in chemistry comprises atomic number and mass number.
Atomic number is written on the top of element and mass number is written at the bottom.
For eg:
If Y is an element that is having atomic number a and mass number x. Then its denotion will be:
ᵃYₓ.
So here ⁹F₁₈.₉₉
Here 18.99 will denote mass number while 9 will denote atomic number.