After 4797 years, how much of the original 250 g of radium-226 remains, if the half-life of radium-226 is 1599 years? *
125 grams
62.5 grams
31.3 grams
O 75.0 grams

31.3grams

Explanation:

The amount of a radioactive element that remains, N(t), can be calculated by using the formula;

N(t) = N(o) × 0.5^{t/t(1/2)}

Where;

N(t) = mass of substance remaining

N(o) = mass of original substance

t(1/2) = half-life of substance

t = time elapsed

From the provided information; N(t) = ?, N(o) = 250g, t(1/2) = 1599 years, t = 4797 years

N(t) = 250 × 0.5^{4797/1599}

N(t) = 250 × 0.5^(3)

N(t) = 250 × 0.125

N(t) = 31.25g

N(t) = 31.3grams

the formula for the conversion of temperature from degree celsius to kelvin is:

the sample of water at is converted to kelvin temperature by using the above formula as:

on comparing the two samples of water at or we can say that at and at respectively. the difference between the temperatures of two samples of water is:

hence, one can say that the sample of water at is greater than the sample of water at by .