Chemistry term 1 Year 11 Flashcards
What is the mass number?
The number of protons plus number of neutrons in the nucleus of an atom. Symbol is A
What does stable in chemistry mean?
A filled outer shell of electrons is generally associated with stability.
Stable as in UNREACTIVE.
What are covalent molecules made up of?
Covalent molecules have the same number of protons as it does electrons.
In intermolecular forces…
…The bigger the number the stronger the forces of attraction.
What are intermolecular forces?
Although molecules are overall neutral in charge, there could possibly be very small electrostatic forces of attraction between protons in nuclei of an atom with electrons in adjacent atoms.
What is a dipole?
Regions of uneven distribution of charge.
Explain the dipole
Dipoles form when random movement of electrons result in the majority of electrons being on one side. Electrons are attracted to positive side. There can be temporary instantaneous dipoles in substances with the same electronegativity. It results in the formation of temporary induced dipoles within its vicinity.
Example of Atomic Weight calculation
Eg. 75.53% Chlorine 35 and 24.47% Chlorine 37
Atomic Weight (Cl)
=75.53/100 x35 + 24.47/100x 37
=35.49
What is a cation?
a positive ion
What is a anion?
a negative ion
How do protons determine the chemistry of an element?
Each proton carries a positive charge, so the number of positively-charged protons will determine the number of negatively charged electrons that the nucleus can ‘hold onto’.
In ionic compounds, what is each cation surrounded by?
A set number of anions
Same applies to each anion with cations
What is a nuclear charge?
- The charge of the nucleus
- Number of protons determines the magnitude of its positive charge
What is the atomic number?
- The number of protons in the nucleus of an element. (determines all the chemistry that it exhibits)
- The symbol is Z
Ions are charged….
- atoms or molecules
2. because they have a different number of protons and electrons
What happens if there are more protons than electrons in an ionic compound?
It has an overall charge of positive
Explain the Sub-atomic particle electron
Symbole is e-
Relative mass is 0
Relative charge - negative
Location - orbiting
Explain the Sub-atmoic particle neutron
Symbol is n
Relative mass is 1
Relative charge - no charge
Location - nucleus
Explain the Sub-atomic particle proton
Symbol is P+
Relative Mass is 1
Relative charge - positive
Location - nucleus
Vibrational kinetic energy
Particles vibrate.
This is a predominant form of kinetic energy of particles in solids.
Rotational kinetic energy
Partuicles might spin on an axis.
Transitional kinetic energy
Particles moving around relative to each other
Define ductile
Drawn out in wire
Define malleable
Can be shaped/flattened into sheets
What is an element?
An element is a substance that cannot be broken down into simpler substances.
What is a compound?
A compound is a substance that can be broken down by chemical reaction.
What are the 4 kinetic particle theories?
- All matter is made of tiny particles
- The particles are constantly moving
- If particles ar heated they gain kinetic energy
- The particles have forces of attraction between them. Different particles have different sized forces of attraction..
What is a lone pair?
Lone pairs are elecrons that ar unshared.
Define Electronegativity
Affinity for electrons
To be a good conductor of electricity you must…
…have charged particles that are able to move freely.
