Fundamentals of Chemistry Flashcards
What 3 major particles form the atom?
List their charges and relative masses.
Proton (+ve charge, mass = 1)
Neutron (no charge, mass = 0)
Electron (-ve charge, mass = 1)
Describe the arrangement of protons, neutrons and electrons in an atom.
Protons + neutrons in nucleus.
Electrons orbit the nucleus and are held in place by electrostatic attractions.
Describe the elemental composition.
Include mass number and atomic number.
Mass number
Element
Atomic number
What is the name of two atoms which:
Contain the same number of protons, different number of neutrons and have different atomic masses.
Isotope
When are atoms most stable?
When their outer-most orbital is full.
When an atom gains/loses electrons, creating a charge, it is known as what?
An ion.
Describe what occurs during ionic bonding.
Electrons are transferred between metals and non-metals.
Describe what happens during covalent bonding.
Electrons are shared between two or more non-metals.
What does the term valency relate to?
The number of covalent bonds an atom can make.
When do dative covalent bonds occur?
When both electrons of a pair are donated by one atom.
Creates one atom with positive charge and one with negative charge because the electron has been left behind and only the nucleus moves (contains protons and neutrons).
What form of bonding produces a charged ion?
Dative covalent bond.
What determines the shape of a covalent bond?
The number of electron pairs in the outer shell of the central atom.
TRUE OR FALSE:
Lone pairs repel more than shared pairs (give an angular structure).
TRUE
Define the word electronegativity.
Measure for attraction for electrons in a bond - capacity to pull.
When do atoms form polar bonds?
Polar bonds are formed when atoms have different electronegative charges -> more electronegative = negative charge.
Dipole example = HCl
