Development of the periodic table - Webflow
Development of the periodic table
1 Describe early attempts to arrange elements in a periodic table.
2 Explain why Mendeleev was able to predict undiscovered elements and their properties.
3 Describe how elements are arranged in the modern periodic table.
Development of the periodic table '
???????1.?1:??????:?????E?:1!?1?1:??:?! ???HF=?:?:! Key words
1:??oI* The periodic table is arranged in I columns called 1gro=up1s.
???I The groups are labelled 1, 2, transition metals, 3, 4, 5, 6, 7 and 0 (or 8).
0
12
34 5 67 1
2
transition metals
3
4
5
6
7
Key
?questions
???I All the elements in a group have similar chemical properties (e.g. group 1
consists of highly reactive metals). As a result they react in the same way. This is because all the elements in a group have the same number of electrons in their outer shell (group 1 metals all have one electron in their outer shell.
20
40
?? The elements in a periodic table are arranged in order of atomic number
calcium
starting with hydrogen at 1. Remember the atomic number is equal to the
number of protons in an atom.
20
40
&?o? TheI rows in a periodic table are called1pe=riod1s. The number of the period
tells you how many energy levels or shells an element has.
Mendeleev and the periodic table
20
40
1:?.*?] Mendeleev started by arranging all the elements in order of increasing
atomic weight.
20
40
?? Mendeleev would switch the order of elements so that they fitted the
calcium
patterns of elements in the same group.
???I Mendeleev also realised that some elements had not been discovered so he
would leave gaps in the periodic table.
I Summary
1 Development of th- e periodic table
=
1 Mendelee- v's period1 ic table
Key words
? t?.iin??t#??iI?if---l:i*:&s H II keteomwennts H'undiscovered poison nothing I .
Key questions
. Mendeleev was able to predict the properties of the undiscovered elements based on the other elements in the group.
i
:.*is. When Mendeleev developed his table, protons had not been discovered. The problem with basing the table on atomic weights is that the elements can appear in the wrong order due to the presence of isotopes.
::*oa Mendeleev also did not include group 0. This is because these elements are not
reactive so had not been discovered.
I Summary
................
................
In order to avoid copyright disputes, this page is only a partial summary.
To fulfill the demand for quickly locating and searching documents.
It is intelligent file search solution for home and business.
Related download
- the periodic table periodic law
- development of the periodic table webflow
- periodic table periodicity
- periodic table questions
- zodiac periodic table activity warner s science website
- chapter 1 periodic classification of elements and periodicity
- periodic table
- 6 the periodic table mr hayward s science page
- learners misconceptions in periodic table an analysis of cognitive
- periodic table of agile principles and practices
Related searches
- the periodic table symbols and names
- memorize the periodic table game
- periods on the periodic table represent elements
- the periodic table song 2018 update lyrics
- groups on the periodic table meaning
- metals in the periodic table list
- what are the periodic table groups
- the periodic table worksheet pdf
- names of the periodic table of elements
- what is the periodic table for kids
- labeling the periodic table worksheet
- learning the periodic table videos