Atomic Structure Flashcards
Define the term atom
The smallest part an element that can exist
Define the term element
One of more than one hundred substances that cannot be chemically interconverted or broken down into simpler substances
Define the term compound
A substance formed from two or more different elements, chemically combined, in fixed proportions
Name the three fundamental particles of an atom
Proton, neutron, electron
What is the relative mass and charge of a proton?
mass = 1, charge +1
What is the relative mass and charge of a neutron?
mass = 1, charge = 0
What is the relative mass and charge of an electron?
mass negligible (1/1800), charge = -1
In an atom, what is the ratio of protons to electrons?
1:1
Define atomic number
The number of protons in the nucleus of an atom
Define mass number
The total number of protons and neutrons in the nucleus of an atom
Define isotope
A chemically identical atom, with the same atomic number but a different mass number
In what order are elements listed in a modern periodic table?
Atomic number
What is a periodic table group?
A vertical group of elements with similar chemical properties
What is a periodic table period?
A row across the periodic table
What information about electrons can be gained from group number?
Number of electrons in the outer shell
What information about electrons can be gained from period number?
Number of shells of electrons
If an atom forms a positive ion what happens?
One or more electrons is lost, up to a maximum of 3
If an atom forms a negative ion what happens?
One or more electrons is gained, up to a maximum of 3
What happens to atomic number and mass number when a positive or negative ion is formed?
Neither change
Why do isotopes of the same element have the same chemical properties?
There electronic structures are identical, so they have the same number of outer electrons
If an element is in group 7, period 2, what is its electron configuration in 2,8,8,8 format? Which element is it?
2,7 Fluorine, F (not flourine!)
If an element is in Group 1, period 4, what is its electron configuration in 2,8,8,8 format? Which element is it?
2,8,8,1 potassium, K
If an element is in group 2, period 3 forms a +2 ion, what is its electron configuration in 2,8,8,8 format? Which element is it formed from?
2,8 magnesium, so forms Mg2+
If an element in group 5, period 2 forms a -3 ion, what is its electron configuration in 2,8,8,8 format? Which element is it formed from?
2,8 phosphorus, so forms P3-
The ions Mg2+ and P3- are isoelectronic, what does this mean?
They have the same electron configuration
Why do the isoelectronic ions Cl- and Na+ not have the same chemical properties?
Their atomic number, and hence number of protons is different.
Element Q forms a sulphate with formula QSO4. What is the electronic configuration of Q using the 2,8,8,8 format?
2,8,2
What is the charge? Nitrate
NO3-
What is the charge? sulphate
SO42-
What is the charge? carbonate
CO32-
What is the charge? ammonium
NH4+
What is the charge? phosphate
PO32-
What is the formula of iron(III) chloride?
FeCl3
What is the formula of ammonium phosphate?
(NH4)3 PO3
Show the numbers of sub-atomic particles in a K+ ion
18e, 19p, 22n
What are the numbers of neutrons and electrons in the 57Fe2+ ion?
31n, 24e
How many neutrons does H+ have
0
Element R is in period 3, it forms a carbonate with the formula R2(CO3)3. What is the electronic configuration of Q using the 2,8,8,8 format? Which element is it?
2.8.3 aluminium
Element T is in period 4, it forms an ammonium salt with the formula NH4T.What is the electronic configuration of Q using the 2,8,8,8 format? Which element is it?
2,8,8,7 bromine
Element X is in period 3, it forms an ammonium salt with the formula (NH4)2 X. What is the electronic configuration of Q using the 2,8,8,8 format? Which element is it?
2,8,6 sulphur
