No of Neutrons =Mass No-No of protons


- Hence it has atomic no 38
The element is Stroncium(Sr)
<span>The constant bombardment of gas molecules against the inside walls of a container produces Pressure.
Explanation:
Pressure is defined as Force per unit Area.
P = F / A
In case of gases, the gas molecules have high Kinetic Energy and they move with high velocity. This cause them to strike against the inside wall of the container. Pressure is directly proportional to temperature. Increase in temperature cause to increase the Kinetic Energy of molecules, Hence, the rate of collisions increases resulting in increasing the pressure.</span>
Answer:
it is necessary to keep our sense organ clean and healthy for if don't clean our sense organ clean we may suffer from many disease like if we don't clean eyes we can't see anything, if we don't clean ear we can't listen anything, and if we don't clean nose it hard for breathing, and if we don't cleanour tounge should be dry and become our breathe smell is very bad, and if we don't clean skin we may suffer from many disease and that may we get cancer also.
The answer to this question would be: 3.125%
Half-life is the time needed for a radioactive molecule to decay half of its mass. In this case, the strontium-89 is already gone past 5 half lives. Then, the percentage of the mass left after 5 half-lives should be:
100%*(1/2^5)= 100%/32=3..125%