Answer11)https://d2vlcm61l7u1fs.cloudfront.net/media%2Fbbf%2Fbbfc5bb1-685f-4eab-874a-b8bb48d164d3%2FphpYI2gJf.png

Answer12)1.Gold 197, mass no(A) = 197 , atomic number (Z)= 79

Atomic no. (Z) = no.of electrons in an atom Therefore no. Of electrons in gold 197=79

No. Of electrons =no. Of protons Therefore no. Of protons in gold 197 is 79

Mass no. (A) = no. Of protons + no. Of neutrons

197 =79+ no. Of neutrons

No. Of neutrons = 197-79= 118

Ans: p=79,N=118,e- =79

2. According to Thomson atomic model famously known as watermelon model, there is a positively charged cloud all over an atom is evenly spread just like pulp of the watermelon and electron are stuck onto this positively charged cloud just like the seeds of the watermelon.

Ans: Hence the best suited Thomson model is model (a)

3. Rutherford experiment was bombardment of alpha particles to a gold foil, where maximum of the alpha rays passed through the gold foil, some deflected to different angles, and even some reflected back. From this he putforth a new theory that had a concept of having a nucleus where in the mass of an atom was concentrated.

Hence the appropriate statement about Rutherford experiment is

Ans: option b. Some alpha particles deflected to large angles as if they had stuck regions of highly positive charge and large mass.

Answer13)https://d2vlcm61l7u1fs.cloudfront.net/media%2Ffb4%2Ffb4ababd-8bd1-4380-be07-d195de05c07d%2FphpqVrqk8.png

Answer14)https://d2vlcm61l7u1fs.cloudfront.net/media%2F1cc%2F1cc56a69-72b1-4d50-b70b-2b6fb61dd09f%2Fphp2RzHnh.png

Answer15)A. Chemical Formula = He

B. Helium is an element

Answer16)https://d2vlcm61l7u1fs.cloudfront.net/media%2F30b%2F30ba6152-486b-47bc-b51a-90a7017f1ef4%2Fphpp8wOSr.png