Answer:
protons = atomic numbermass number = protons + neutronsatomic number = mass number - neutrons = 78-38 = 40
Explanation:
Answer:4
Explanation:
As shown in the image attached, a face-centred cubic structure has 8 atoms at the corners and 6 face center atoms.
Each corner atom contributes to eight cell, so per unit cell 1/8 ×8 =1atom
Face center atoms contributes to two unit cells 1/2 × 6=3atoms
Total atoms =3+1=4atoms
Therefore the atoms in Al FCC per unit cell is 4
Given :
The distance between a point charge and a neutral atom and is multiplied by a factor of 5.
To Find :
By what factor does the force on the neutral atom by the point charge change.
Solution :
We know, electrostatic force between two object is directly proportional to product of charge and inversely proportional to distance between them.
Now, charge in neutral atom is 0 C.
So, the electrostatic force between two of them is also 0 N.
Therefore, by changing distance between the charge the forces did no change ( it remains zero).