Tha half-life of `U^(238)` against alpha decays is `1.42 xx 10^(17)s`.How many disintengrations per second occur in 1 g of `U^(238)`?Given,Avogadro umber `=6.02 xx 10^(23) mol^(-1)`.

The half life of "_92^238U against alpha-decay is 1.5 xx 10^17s . What is the activity of a sample of "_92^238U having 25 xx 10^20 atoms?

Half life of "_92^238U against alpha-decay is 4.5 xx 10^9 years. Calculate activity of 1 g of sample "_92^238U .

The half-life of "_92^238U undergoing alpha decay is 4.5 xx 10^9 years. Calculate the activity of 10 g sample of "92^238U .

The half life of "_92^238U undergooing alpha today decay is 4.5 xx 10^9 years . Calculate the activity of 5 g sample of "_92^238U .

Mass of one atom of the element A is 3.9854 xx 10^(-23)g . How many atoms are contained in 1g of the element A ?

What is the drift velocity of electrons in a silver wire of length 1 m, area of cross-section 3.14 xx 10^-6m^2 and carrying a current of 10 A. Given, charge on electron = 1.6 xx 10^-19C , Avogadro number = 6.02 xx 10^23 atomic weight of silver = 108 and density of silver = 10.5 xx 10^3 kg m^-3 .

Suppose 2 kg of sugar contains 9 xx 10^6 crystals. How many sugar crystals are there in : 1.2 kg of sugar?