<h3><u>Answer;</u></h3>
<em>Electrons </em>
<h3><u>Explanation;</u></h3>
- <em><u>Thomson contributed to the model of an atom by discovery of </u></em><em><u>electrons </u></em><em><u>and thus proving the existence of sub-atomic particles in an atom. </u></em>
- <u><em>Thomson used cathode ray tube, and demonstrated that cathode rays were negatively charged.</em></u> According to his model normally known as the plum pudding in which he stated that an atom is composed of electrons as subatomic particles that are surrounded by positive charges to balance the electrons.
Answer:

Explanation:
In a uniform circular motion, since a complete revolution represents 2π radians, the angular velocity, which is defined as the angle rotated by a unit of time, is given by:

Here T is the period, that is, the time taken to complete onee revolution:

Replacing (2) in (1):

First, we assume this as an ideal gas so we use the equation PV=nRT. Then, we use the conditions at STP that would be 1 atm and 273.15 K. We calculate as follows:
PV= nRT
PV= mRT/MM
1 atm (.245 L) =1.30(0.08206)(273.15) / MM
MM = 118.94 g/mol <--- ANSWER
Answer:
The weight acting upon a object
Explanation: