Question

The total number of neutrons in dipositive zinc ion with mass number 70 is

Solution

Correct option is

40

Z  for Zn = 30

No.of neutrons = A – Z

                         = 70 – 30

                         = 40

SIMILAR QUESTIONS

Q1

The neutron separation energy is defined to be the energy required to remove a neutron from a nucleus. Obtain the neutron separation energy of the nucleus of Given : mass of  atom = 40.962278 u, mass of  atom = 39.962591 u, mass of neutron = 1.008665 u and .   

Q2

The nucleus  decays by -emission. Write down the decay equation and determine the maximum kinetic energy of the emitted electron. The atomic masses of  are 22.994466 u and 22.989770 u respectively.

Q3

When a deuteron  of mass 2.0141 u and negligible kinetic energy is absorbed by a lithium  nucleus of mass 6.0155 u, the compound nucleus disintegrates spontaneously into two alpha particles, each of mass 4.0026 u. Calculate the energy in joule carried by each alpha particle.    

Q4

If the half lives of a radioactive element for α and β decay are 4 yrs and 12 yrs respectively, the ratio of their activities after six yrs will be

Q5

Half life of a radioactive sulistance A is 4 days. The probability that a nucleus will dacay in two half lives is

Q6

The half life of  The time taken for the radioactivity of a sample of  to dacay to 1/6 th  of its initial value is:

Q7

The half life of 131I is 8 days. Give a sample of 131I at time t = o, we can assert that

Q8

The mass of one mole of electrons is

Q9

The increasing order for  the values of e/m is

Q10

A radioactive nucleus is leing produed at a constant rate  per second. Its decay constant is λ. If No. are the number of nuclei at time t = 0, then  themanimum no, of nuclei