In 1880s, how were elements grouped?
How were elements categorised?
-Physical and chemical properties, and Relative Atomic Mass
How is the modern periodic table arranged?
Why was it difficult at the time to arrange the periodic table by proton number?
-Protons and electrons were not known, they could only measure relative atomic mass
In 1817, who attempted to group similar elements?
What were Johann Döbereiner’s groups called?
Which 3 elements did he notice had similar properties?
Who was John Newlands? What did he do/notice?
-If he arranged elements in order of mass, similar elements appeared at regular intervals – every eighth element was similar. Known as octaves
Who created the first accepted version of the Periodic Table in 1869?
How did Dmitri Mendeleev’s periodic table differ from John Newlands?
-Left gaps in the table where next element didn’t seem to fit
What was the advantage of Dmitri Mendeleev leaving gaps?
-Keeping elements with similar chemical properties in the same group
-Predicting properties of undiscovered elements in the gaps
How was Dmitri Mendeleev proved right?
-When elements were later discovered (germanium, scandium, gallium) with properties that matched Mendeleev’s predictions
Who made the MODERN periodic table in 1914?
How did Henry Moseley arrange his elements?
-Noble gases added (Group 0)
What was the final big chance by Glenn Seaborg?
-Suggested how the f-block elements fit into the Periodic Table
In the modern Periodic Table what represents to the rows and columns?
What is the similarity of all elements in the same period?
-Same number of electron shells (if you don’t worry about the sub-shells)
How many electron shells do the elements in Period 1?
What is the similarity of all elements in the same group? What does this mean?
-Same number of electrons in their outer shell
-Similar physical and chemical properties
How many electrons in the outer shell of Group 4 atom?
How many ‘block’s, can the periodice table be split into? What are they?
-s, p, d, f
Is 2p6 a complete sub-shell? Why?
-Only 6 electrons occupy a p sub shell
What does periodicity mean?
-Trends that occur (in physical and chemical properties) across periods?
What name is given to trends that occur across periods in terms of physical and chemical properties?
Metal to non-metal is a trend that occurs going **** to ***** in each period?
-Left to right
Name a factor that decreases across a period
Why does atomic radius decrease across a period?
-As the number of protons increases, the positive charge of the nucleus increases. Electrons are pulled closer to the nucleus, making atomic radius smaller
Name a factor the increases across period
Why does ionisation…