Chemistry - Atoms, Bonds and Groups - F321 - The Periodic Table (3) Flashcards
Who introduced the letter based symbols for elements?
Jons Jakob Berzelius introduced the letter based symbols for elements.
Who proposed the ‘law of triads’?
Johann Wolfgang Dobereiner proposed the ‘law of triads’.
In what year did Johann Wolfgang Dobereiner propose the ‘law of triads’?
In 1829 Johann Wolfgang Dobereiner proposed the ‘law of triads’.
What is the ‘law of triads’?
The ‘law of triads’ states that the middle element of three elements has properties that are an average of the other two members of the triad when ordered by atomic weight.
Who developed an early form of the periodic table arranged in a cylinder in increasing atomic weight and similar properties aligned vertically?
Alexandre Emile Béguyer de Chancourtois developed an early form of the periodic table arranged in a spiral on a cylinder in increasing atomic weight and similar properties aligned vertically.
Who was the first person to devise a periodic table arranged in order of atomic weight?
John Newlands was the first person to devise a periodic table arranged in order of atomic weight.
What was John Newlands the first person to do?
John Newlands was the first person to devise a periodic table arranged in order of atomic weight.
In what year was Mendeleev’s periodic table published?
Mendeleev’s periodic table was published in 1869.
Who published a periodic table about a year after Mendeleev, unaware of his work?
Julius Lothar Meyer independently published his own periodic table about a year after Mendeleev, unaware of his work.
Who determined the atomic number for each of the elements?
Henry Moseley determined the atomic number for each of the elements.
What elements are the semi-metals or metalloids?
Boron, silicon, germanium, arsenic and tellurium are the semi-metals or metalloids.
Define periodicity.
Periodicity is a regular periodic variation of properties of elements with atomic number and position in the periodic table.
What elements will have the same number of electrons in their outer shell?
Elements in the same group will have the same number of electrons in their outer shell.
In general ionisation energies …….. across each period.
In general ionisation energies increase across each period.
Down a group, the first ionisation energies ……….
Down a group, the first ionisation energies decrease.
From group one to group four there is a general ………. in boiling points.
From group one to group four there is a general increase in boiling points.
From group four to five there is a ……….. in boiling point.
From group four to five there is a sharp decrease in boiling point.
From group five to zero ……… boiling points.
From group five to zero they have comparatively low boiling points.
Group 2 elements are the ………
Group 2 elements are the alkaline earth metals.
Group 2 elements have reasonably ……. melting and boiling points.
Group 2 elements have relatively high melting and boiling points.
Group 2 elements have ……. densities.
Group 2 elements have low densities.
Group 2 elements form what coloured compounds?
Group 2 elements form colourless compounds.
Which groups comprise the s block of the periodic table?
Groups 1 & 2 comprise the s block of the periodic table.
As you move down group 2 the elements react ……. with water.
As you move down group 2 the elements react more vigorously with water.
The metals further down group 2 are ….. soluble in water.
The metals further down group 2 are more soluble in water forming more alkaline solutions.
Define thermal decomposition.
Thermal decomposition is the breaking up of a chemical substance with heat into at least two chemical substances.
Group 2 carbonates become more difficult to thermally decompose further …….. the group.`
Group 2 carbonates become more difficult to thermally decompose further down the group.
Halogens have relatively ….. melting and boiling points.
Halogens have relatively low melting and boiling points.
There are ….. van der Waals’ forces further down the group.
There are more van der Waals’ forces further down the group due to an increase in the number of electrons.
Group 7 is in the …. block of the periodic table.
Group 7 is in the p block of the periodic table.
Define a displacement reaction.
A displacement reaction is a reaction in which a more reactive element displaces a less reactive element from an aqueous solution of the latter’s ions.
Define disproportionation.
Disproportionationation is tthe oxidation and reduction of the same element in a redox reaction.
Chlorine reacts with water to form what?
Chlorine reacts with water to form a mixture of two acids: hydrochloric acid and chloric (I) acid.
What colour is chlorine in water?
Chlorine is pale green in water.
What colour is bromine in water?
Bromine is orange in water.
What colour is iodine in water?
Iodine is brown in water.
What colour is chlorine in cyclohexane?
Chlorine is pale green in cyclohexane.
What colour is bromine in cyclohexane?
Bromine is orange in cyclohexane.
What colour is iodine in cyclohexane?
Iodine is violet in cyclohexane.
What symbol is frequently used to represent any halogen?
x is the symbol frequently used to represent any halogen.
TRUE or FALSE
Halide compounds are mainly very stable.
TRUE!
Halide compounds are mainly very stable.
What are crystals of calcium fluoride (CaF2) also known as?
Crystals of calcium fluoride are also known as fluorite or fluorspar.
What are crystals of calcium fluoride used for?
Crystals of calcium fluoride are used to make lenses to focus infrared light.
What could the potential environmental implications of the chlorination of water be?
Chlorine could react with organic matter to form traces of chlorinated hydrocarbons, which are a potential carcinogen.
What colour is a silver iodide preciptate?
A silver iodide precipitate is yellow.
I am yellow
What colour is a silver bromide precipitate?
A silver bromide precipitate is cream.
Brill cream
What colour is a silver chloride precipitate?
A silver chloride precipitate is white.
Chalky white
On addition of ammonia to silver chloride what happens?
Silver chloride is soluble in even dilute ammonia.
On addition of ammonia to silver bromide what happens?
Silver bromide is soluble in concentrated ammonia.
On addition of ammonia to silver iodide what happens?
Silver iodide is insoluble in even concentrated ammonia.
Define a precipitation reaction.
A precipitation reaction is the formation of a solid from a solution during a chemical reaction. Precipitates are often formed when two aqueous solutions are mixed together.