The Periodic Table Flashcards
An element on a periodic table
is a substance that cannot be split into simpler substances by chemical means
In what way are elements arranged on the periodic table
Increasing atomic number
Why are the elements on the periodic table arranged this way
each element has one more proton then the element before
Columns on a periodic table are called
Groups
Rows on a periodic table are called
Periods
What chemist was the first to define the meaning of the term “element”
Robert Boyle
Who discovered what is known as electrolysis
Humphrey Davy
What elements did Humphrey Davy discover
Potassium,Sodium,Calcium
What is Dobereiners Triads
triad is a group of 3 elements with;
1.similar chemical properties
2.atomic weight of the middle element is approximately equal
3.to the average of the other 2
Whats newlands octaves
Are arrangements of elements in which the first and eighth elements,counting from a particular element have similar properties
How did newlands “law of octaves” break down
He didn’t leave any gaps for undiscovered elements
Who was given credit for the finding of the periodic table
Meneleev
What is Mendeleev periodic law
When elements are arranged in order of increasing atomic weight, the property of these elements recur periodically
What did Mendeleev do with the periodic table
He left gaps undiscovered elements
What did Henry Mosley do
Placed elements in order of atomic number, rather than atomic mass
Modern periodic table
When elements are arranged in order of increasing atomic order, the properties of the elements recur periodically
What do groups [columns] do
Tells us the number of electrons in the outermost shell [highest occupied energy level]
What do periods [rows] do
The period tells us the number of shells the elements has
What is an ion
An ion is an atom that has gained or lost electrons
In larger atoms is easier to remove electron, How?
Distance-further from the nucleus
Shielding-more electrons in between outer electrons and nucleus
How many ions can transition metals form?
More then 1
What tells us the charge of an ion?
Roman numerals e.g Copper (II) Cu2+
What is an isotope?
Are atoms of the same elements which are a different mass number due to number of neutrons
What is relative atomic mass (Ar)?
Is the average mass numbers of the isotopes of the elements as they occur naturally
