Which element has no stalbe isotopes: 82Pb, 27Co, 51Sb or 90Th?

You can go to www.webelements.com, click on the element and scroll down the left side to isotopes. There you can view the natural and radioactive isotopes of the element.

90th

To determine which element has no stable isotopes, we need to check the stability of the isotopes of each of the given elements: 82Pb, 27Co, 51Sb, and 90Th.

To do this, we can refer to the isotope table or use a reliable source such as a periodic table with isotope information. In this case, we can refer to the periodic table.

Starting with 82Pb (lead), we look for the stable isotopes of lead. Stable isotopes are those that do not undergo radioactive decay. By checking the periodic table, we find that lead has four stable isotopes: Pb-204, Pb-206, Pb-207, and Pb-208. So, 82Pb has stable isotopes.

Moving on to 27Co (cobalt), we search for the stable isotopes of cobalt. From the periodic table, we find that cobalt has one stable isotope: Co-59. So, 27Co has a stable isotope.

Next, we examine 51Sb (antimony) for its stable isotopes. According to the periodic table, antimony has two stable isotopes: Sb-121 and Sb-123. Therefore, 51Sb also has stable isotopes.

Finally, we consider 90Th (thorium) and its stable isotopes. Referring to the periodic table, we find that thorium has only one stable isotope: Th-232. Therefore, 90Th also has a stable isotope.

In conclusion, out of the given elements, none of them have no stable isotopes. All of the elements mentioned - 82Pb, 27Co, 51Sb, and 90Th - have at least one stable isotope.