WEEKLY WHINE

The Universe’s first periodic table rankings

There now follows a ranking of the top periods of the periodic table. Criteria included prevalence, usefulness, and importance of the elements found in each period.

1. Period 1: Contains only hydrogen and helium. Helium is rare on Earth, but hydrogen is found in water, ammonia, and nearly all organic compounds. It is also the most prevalent element overall in the Universe, and it is fused to serve as the Sun’s energy source. Scientists, after all, have found that the Sun is a huge atom smashing machine.
2. Period 2: Contains crucial elements like carbon, oxygen, and nitrogen. Lithium, the lightest alkali metal, is so reactive that when in its pure state, it must be stored in mineral oil. It is particularly useful in rechargeable batteries.
3. Period 3: Contains important elements like sodium, aluminum, silicon, and phosphorus. Behind oxygen, aluminum and silicon are the most prevalent elements in Earth’s crust. Silicon’s semiconducting properties make it extraordinarily useful in transistors and integrated circuits, which are found in nearly all modern devices.
4. Period 4: Contains important elements like potassium and germanium, as well as the lightest transition metals, such as titanium, iron, cobalt, and zinc. Iron is used in many construction projects, both in its pure form and as steel. Several cobalt salts are brightly coloured and have been used to make pigments for paints and glass.
5. Period 5: Contains interesting elements like iodine, tin, silver, and cadmium. Iodine, the heaviest of the elements essential to life, is found in thyroid hormones; today, the primary source of iodine for most humans is in iodised salt. Technetium is the lightest element not naturally found on Earth.
6. Period 6: Contains interesting elements like lead, gold, mercury, and cesium. Lead was previously used in plumbing and paints, but it causes neural damage and is no longer used for these purposes. Also includes the lanthanides, a group of chemically similar rare earth elements used in superconductors and catalysts.
7. Period 7: Contains interesting elements like radium, uranium, and plutonium. Uranium and plutonium are used in nuclear reactors and weapons, and plutonium is also used as a power source in pacemakers and on deep space probes, like the Voyagers and Cassini. The elements more massive than plutonium are not naturally found on Earth; all, up to and including oganesson, have been synthesised in the laboratory.