1g of a radio active substance disintegrates at the rate of 3.7× 10^10 disintegrations per second.The atomic mass of the substance is 226.Calculate its mean life.

1g of a radioactive substance disintegrates at the rate of 3.7xx10^(10) disintegrations per second. The atomic massof the substance is 226. Calculate its mean life.

One gram ofo a radioactive substance disintegrates at the rate of 3.7 xx10^(10) disintegarations per second. The atomic mass of the subsatnce is 226 . Calculate its mean life.

(a) A radioactive sample has 6.0 xx 10^(18) active nuclei at a certain instant. How many of these nuclei will still be the same active state after two half-lives? (b) Radioactive phosphours -32 has a half-life of 14 days. A source containing this isotope has an initial activity of 10muCi . (i) What is the activity of the source after 42 days? (ii) What time elapse before the activity of the source falls at 2.5muCi ? (c) 1g of a radioactive substance disintergrates at the rate of 3.7 xx 10^(10) dps . The atomis mass of the substance is 226 . Calculate its mean life.

When the quantity of a radioactive substance is increased two times, the number of atoms disintegrating per unit time is

If 3//4 quantity of a radioactive substance disintegrates in 2 hours, its half - life period will be