<span> 1.the atom has 7 neutrons and 8 protons....
because the positively charged particles are the protons ...and 8 is also the atomic number ...so number of neutrons can be calculated by subtracting </span>atomic number from the mass number...which gives us the neutrons 7 ...
Hope it helps !!!
I cannot see all the questions, what is 18,19 and 21? (:
<span>A Conducting Sphere Is On Top Of An Insulating Stand. So A Negatively Charged Tube Is Brought Near The Neutral Sphere Then It Forces Electron Movement From The Left To The Right Side Of The Sphere. Once Touched By The Ground, The Electrons Leave The Sphere. When The Tube Is Moved Away, There's An Overall Positive Charge Left On The Sphere.</span>
Answer:
The number of excess electrons on each sphere is 759
Explanation:
Given that,
distance , d = 20 cm
= 0.20 m
let the number of electrons is n
Electric force (F) = k × (n × e)² /d²
3.33 × = 9 × × (n × 1.602 × )² /0.2²
solving for n
n = 759