Which isotope pairs were originally used to determine the age of the Earth from meteorites?Be specific and be sure to write the numbers and the elements here as listed in Table 1. Table 1. Pairs of radioactive isotopes and representative half-lives as well as sample materials dated.Half-Lives (T1½)Materials Dated4.5 billion years713 million years1.3 billion years5730 yearsParent Isotope (P) Daughter Isotope (D)Uranium-238Uranium-235Potassium-40Carbon-14% Parent10091.7Lead-206Lead-207Argon-40Nitrogen-14How was this discovered? How do we know if an object is radioactive? The presence of radioactive atomscan be determined using a Geiger Counter as the energy and subatomic particles released during the decayof a radioactive parent to a daughter is detected. The early work of studying radioactivity showed that theamount of radioactive atoms seen or heard by the clicks on a Geiger Counter was proportional to the amountof radioactive atoms in the rock being measured. Now that we know the constant decay rates for differentisotope pairs from Table 1 (as noted by T for the half-lives of these radioactive elements), we candetermine the half-lives that have elapsed from parent to daughter ratios... and next calculate ages of rocks!84.170.75035.425HOW TO DETERMINE THE AGE OF ROCKSThe number of parent atoms decrease as daughter atoms increase for each half-life that has elapsed.Thus, older rocks have more daughter product as more decay has occurred. The first step then is todetermine the % parent compared to the % daughter as done before. Geologists can measure the amount ofdaughter atoms in a rock, and subtract from 100% to determine the proportion of parent atoms remaining.and then assess how many half-lives have elapsed using Table 2. Then the age equation can be used tocalculate the age of a rock for a specific pair of isotopes given the decay constant and half-lives that haveelapsed. For example, a rock that has 50% Carbon-14 and 50% Nitrogen-14 is 5730 years old (as it is 1 xT ½ for that isotope pair). If a rock instead had 75% Nitrogen-14, TWO half-lives have elapsed (parentmaterial is divided in half 2x leaving only 25% Carbon-14), and so the rock is 5730 x 2 = 11,460 years old.Table 2. Decay parameters for all radioactive decay pairs and the age equations for half-lives elapsed.Half-Lives Elapsed12.56.2% Daughter08.315.929.3zirconzircon5064.67587.593.8biotite, muscovite, whole volcanic rockshells, wood, bones, limestone01/8¼½11½234Age Equation0xT½0.125 x T ½0.250 x T ½0.500 x T ½1.0 x T ½1.5 x T ½2.0 x T ½3.0 x T ½4.0 x T ½

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The decay of long-lived radioactive isotopes of elements found naturally in rocks and minerals,…

Which isotope pairs were originally used to determine the age of the Earth from meteorites? Be specific and be sure to write the numbers and the elements here as listed in Table 1.