Potassium, aluminum, silicon, magnesium neon
Mendeleev's periodic table
Dmitri Mendeleev
Like many scientists working at the end of the 19th-century the Russian chemist Dmitri Mendeleev (1834-1907) was looking for ways to organise the known elements. Mendeleev published his first periodic table of the elements in 1869.
Features of Mendeleev's tables
Mendeleev arranged the elements in order of increasing relative atomic mass. When he did this he noted that the chemical properties of the elements and their compounds showed a periodic trend. He then arranged the elements by putting those with similar properties below each other into groups. To make his classification work Mendeleev made a few changes to his order:
he left gaps for yet to be discovered elements
he switched the order of a few elements to keep the groups consistent
Explanation: A river drainage basin is an area drained by a river and all of its tributaries. A river basin is made up of many different watersheds. A watershed is a small version of a river basin. Every stream and tributary has its own watershed, which drains to a larger stream or wetland.
Answer:
A change in speed and direction between atleast one of the objects
Explanation:
