This is the smallest unit of an element that can exist.
What is an atom?
Before the discovery of the electron, atoms were thought to be these.
What are tiny spheres that could not be divided?
Protons have this type of electrical charge.
What is a positive charge?
This group contains the noble gases.
What is Group 0?
Halogens
What other name is given to group 7 elements?
This table arranges elements in order of increasing atomic number and groups elements with similar properties together.
What is the periodic table?
This model of the atom was proposed after the discovery of the electron and depicted the atom as a ball of positive charge with electrons embedded in it.
What is the plum pudding model?
In an atom, the number of protons is equal to the number of these particles, resulting in no overall electrical charge.
What are electrons?
Elements in this group have a single electron in their outer shell and are known for their high reactivity.
What is Group 1 (alkali metals)?
When a more reactive element takes the place of another in a compound
What is a displacement reaction?
This type of substance is made up of two or more elements chemically combined in fixed proportions.
What is a compound?
The results of this experiment led to the conclusion that the mass of an atom is concentrated in a charged nucleus.
What is the alpha particle scattering experiment?
This term refers to the number of protons in an atom's nucleus and determines the element's identity.
What is the atomic number?
This scientist is credited with creating the first periodic table by arranging elements based on atomic weights and leaving gaps for undiscovered element
Who is Dmitri Mendeleev?
Lithium hydroxide and hydrogen
What is formed when lithium reacts with water?
These can be separated by physical processes like filtration and distillation.
What are mixtures?
This scientist adapted the nuclear model by suggesting that electrons orbit the nucleus at specific distances.
Who is Niels Bohr?
Almost all of an atom's mass is concentrated in this part of the atom.
What is the nucleus?
Diatomic molecules
What name is given when 2 atoms of the same element are joined together?
Inert
What is another name for unreactive?
This technique separates substances based on their different boiling points.
What is fractional distillation?
This scientist's experimental work provided evidence for the existence of neutrons within the nucleus.
Who is James Chadwick?
These atoms of the same element have different numbers of neutrons.
What are isotopes?
They get more reactive as the single electron is further away from the nucleus
What happens to reactivity as you go down group 1?
squeaky pop test
What is the test for hydrogen?