Advertisements
Advertisements
Question
A certain nucleus has a mass number 20 and atomic number 9. Find the number of neutrons and protons present in it.
Advertisements
Solution
(i) Number of neutrons = Mass number – Atomic number
= 20 – 9 = 11
(ii) Number of protons = Atomic number = 9.
RELATED QUESTIONS
Under which conditions does the nucleus of an atom tend to radioactive?
Name a gas caused by the Greenhouse effect
Radiations given out from a source when subjected to an electric field in a direction perpendicular to their path are shown below in the diagram. The arrows show the path of the radiation A, B and C. Answer the following questions in terms of A, B and C.
1) Name the radiation B which is unaffected by the electrostatic field.
2) Why does the radiation C deflect more than A?
3) Which among the three causes the least biological damage externally.
4) Name the radiation which is used in carbon dating.
What do you mean by Mass number.
A nucleus of an element X which has the symbol `""_84^202` X emits an alpha particle and then a beta particle. The final nucleus is `""_"b"^"a"` Y Find a and b.
What do you mean by electron emission?
Unit of radioactivity is _______
The mean lives of a radioactive substance are 1620 and 405 years for β-emission and β-emission respectively. The time after which three fourth of a sample will decay if it is decaying both by β-emission and β-emission simultaneously will be ______ years.
(Take ln 2 = 0.693)
A radioactive element is placed in an evacuated chamber. Then the rate of radioactive decay will ______.
