The half-life period of RaB`(._(82)Pb^(214))` is `26.8 min`. The mass of one curie of RaB is

The half-life period of a radioactive substance is 5 min . The amount of substance decayed in 20 min will be

The half-life period of a radioactive substance is 5 min . The amount of substance decayed in 20 min will be

The half life period of Pb^(210) is 22 years. If 2 g of Pb^(210) is taken, then after 11 years the amount of Pb^(210) will be present is

(a) On analysis a sample of uranium ore was found to contian 0.277g of ._(82)Pb^(206) and 1.667g of ._(92)Pb^(206) and 1.667g of ._(92)U^(238) . The half life period of U^(238) is 4.51xx10^(9) year. IF all the lead were assumed to have come from decay of ._(92)U^(238) , What is the age of earth? (b) An ore of ._(92)U^(238) is found to contain ._(92)U^(238) and ._(82)Pb^(206) in the weight ratio of 1: 0.1 The half-life period of ._(92)U^(238) is 4.5xx10^(9) year. Caluculate the age of ore.

The weight of 1 curie ._(82)Pb^(214) (t_(1//2)=26.8 min) in grams is

The half-life period of a reaction is 100 min In 400 min the initial concentration of 2.0g will become.

If the half-life period of a first order reaction is 138.6 min, then the value of decay constant for the reaction will be ("in min"^(-1))

The half life period of a reaction is 100 min . In 400 min the intitial concentration of 2.0 g will become :