<u>Answer:</u> The number of electrons in given amount of silver are 
<u>Explanation:</u>
To calculate the number of moles, we use the equation:

We are given:
Given mass of silver = 7.1 g
Molar mass of silver = 107.87 g/mol
Putting values in above equation, we get:

Number of electrons in 1 atom of silver = 47
According to mole concept:
1 mole of an element contains
number of particles
So, 0.066 moles of silver will contain = -
number of electrons
Hence, the number of electrons in given amount of silver are 
Tooth fillings are often made of gold or porcelain because these materials are nonreactive.
b. nonreactive.
<h2>
Speed with which it return to its initial level is 100 m/s</h2>
Explanation:
We have equation of motion v² = u² + 2as
Initial velocity, u = 100 m/s
Acceleration, a = -9.81 m/s²
Final velocity, v = ?
Displacement, s = 0 m
Substituting
v² = u² + 2as
v² = 100² + 2 x -9.81 x 0
v² = 100²
v = ±100 m/s
+100 m/s is initial velocity and -100 m/s is final velocity.
Speed with which it return to its initial level is 100 m/s
Answer:
7.401 * 10^(-15) N
Explanation:
30 electrons will have a charge:
30 * -1.6022 * 10^(-19) C
= - 4.806 * 10^(-18) C
The relationship between electric field and electric force is:
E = F/q
This means that force, F, is
|F| = |E|*|q|
|F| = |1540| * |-4.806 * 10^(-18)|
|F| = |-7401.24 * 10^(-18)|
|F| = 7.401 * 10^(-15) N