Question

FAN AND MEDAL FOR BEST ANSWER!!!

Answer 1

1 berry, 1 orange and 2 lemons

Answer 2

haha I like banana XD

Answer 3

Don't make fun of me I will report you!

Answer 4

What conclusion can be drawn about the relationship between the arrangement of elements on the periodic table and the patterns observed in their properties?

Answer 5

Electronic structure and the arrangement of elements in the Periodic Table

All substances are made up of one or more of the different types of atoms we call elements and the elements identity is solely determined by the atomic number of protons.
Hydrogen, 1, H, the simplest element atom, does not readily fit into any group.
A Group is a vertical column of like elements e.g. Group 1 The Alkali Metals (for full GCSE notes on Li, Na, K etc.), Group 7/17 The Halogens (for full GCSE notes on F, Cl, Br, I etc.) and Group 0/8/18 The Noble Gases (for full GCSE notes on He, Ne, Ar etc.).
Apart from hydrogen (doesn't really fit in any group), and helium (*), the Group number equals the number of electrons in the outer shell and the number of electron shells used equals the Period number, e.g. chlorine's electron arrangement is 2.8.7, the second element down in Group 7 on period 3. So after helium, elements in the same group have the same outer electron structure.
(*) Although helium can't have 8 outer electrons like the rest of Group 0, its outer shell of 2 electrons is complete according to the electron shell rules, just like neon and argon etc. and therefore has the same chemical and physical properties.
The elements in a group tend to have similar physical and chemical properties because of their similar outer shell electron structure.
A Period is a horizontal row of elements with a variety of properties, changing from very metallic elements on the left to non-metallic elements on the right. A period starts when the next electron goes into the next available main energy level or shell (Group 1 alkali Metals). The period ends when the main energy level is full ie reached the Group 0 Noble Gases.
All the elements on the same period use the same number of principal electron shells, and this equals the period number (e.g. sodium's electron arrangement 2,8,1, the first element in Period 3).
The first element in a period is when the next electron goes into the next available electron shell or energy level (i.e. 1 electron in the outer shell, after H it is the Group 1 Alkali Metals like sodium 2.8.1).
The last element in a period is when the outer shell is full resulting in a very unreactive element, the Group 0 Noble Gases e.g. argon 2.8.8. The next electron for the next element goes into the next highest level (shell) available, and so starts the next period with a group 1 element again, periodicity - a very similar element every so often - but governed by the electron rules.
So in terms of electrons ....
Period 1 is elements 1-2, H (1) to He (2)
Period 2 is elements 3-10, Li (2,1) to Ne (2,8)
Period 3 is elements 11-18, Na (2.8.1) to Ar (2.8.8)
Period 4 is elements 19-36, starts with K (2,8,8,1) and Ca (2,8,8,2) and finishes with the Noble Gas Kr (2,8,18,8).
Note that the number of shells containing electrons is equal to the period number.
The similarities (e.g. same Group) or differences (e.g. across a period) of the properties of the elements can be explained by the electronic structure of the atoms.
From Period 4 onwards the length of a period significantly increases because it includes horizontal series of similar metals with their own characteristic physical and chemical properties e.g. Transition Metals (detailed GCSE notes on Fe, Cr, Cu etc.)

Answer 6

WHAT MADE THE TABLE PERIODIC? The value of the table gradually became clear, but not its meaning. Scientists soon recognized that the table's arrangement of elements in order of atomic weight was problematic. The atomic weight of the gas argon, which does not react readily with other elements, would place it in the same group as the chemically very active solids lithium and sodium. In 1913 British physicist Henry Moseley confirmed earlier suggestions that an element's chemical properties are only roughly related to its atomic weight (now known to be roughly equal to the number of protons plus neutrons in the nucleus). What really matters is the element's atomic number—the number of protons its atom carries, which Moseley could determine with X-rays. Ever since, elements have been arranged on the periodic table according to their atomic numbers. The structure of the table reflects the particular arrangement of the electrons in each type of atom. Only with the development of quantum mechanics in the 1920s did scientists work out how the electrons arrange themselves to give the element its properties.