In a sample of pitchbende, the atomic ratio of `.^(206)Pb : .^(238)U` is 0.23 : 1. Calculate the age of the mineral if half life of uranium is `4.5 xx 10^(9)` years. Assume that all lead has originated from uranium.

A sample of uranium mineral was found to contain Pb^(208) and U^(238) in the ratio of 0.008 : 1. Estimate the age of the mineral (half life of U^(238) is 4.51 xx 10^(9) years).

In a smaple of rock, the ration .^(206)Pb to .^(238)U nulei is found to be 0.5. The age of the rock is (given half-life of U^(238) is 4.5 xx 10^(9) years).

A uranium mineral contains .^(238)U and .^(206)Pb in the ratio of 4 : 1 by weigh. Calculate the age of the mineral, t_(1//2) .^(238)U = 4.5 xxx 10^(9) years. Assume that all the lead present in the mineral is formed from disintegration of .^(238)U .

The number of U^(238) nuclei in a rock sample equal to the number of Pb^(206) atoms. The half life of U^(238) is 4.5xx10^(9) years. The age of the rock is

Find the amount of ""_(92)U^(238) required to produce a-particles of 20 millicurie strength. The half-life of ""_(92)U^(238) is 4.5 xx 10^(9) years.

On analysis a sample of .^(238)U ore was found to contain 20.6g of ._(82)^(206)Pb ad 23.8g of ._(92)^(238)U . The half life period .^(238)U is 4.50 xx 10^(9) years. If all the lead were assumed to have come from decay of ._(92)^(238)U , what is the age of the ore?