Christmas Exam Flashcards
Atomic number
No of protons in an atom of that same element
What is an electron
Subatomic particle, located in electron cloud of an atom
Orbital
Region of space within the nucleus of an atom with a high probability of finding an electron
Cathode rays
Streams of negatively charged rays called electrons
State One limitation of Arrhenius acid base theory
NH3 cannot be considered a base
Acid according to Arrhenius
Substance that dissociates in water to give protons
Acid according to bronsted Lowry
Proton donor
What is a conjugate pair
Two species that differ by a proton
Knocking
Results from petrol auto igniting
Octane number
Measure of a tendency of a fuel to resist knocking
Define heat of formation
Heat change when 1 mole of a substance is formed from its elements in their standard states
Define fractional distillation
Separation into components according to molecular size
Hess law
Heat change for a reaction depends only on initial and final states
Atomic theory
matter is composed of tiny, indivisible particles called atoms that can neither be created nor destroyed.
Why might an electron not occupy n= 1
Excited
What colour can be seen when electron jumps from n= 3 to n= 2
Red
What are the lines on the hydrogen emission spectra called
Balmer
How many orbitals are associated with n = 2
4
What is the max no of electrons that can occupy n = 3
18 (2 + 8 + 8)
What term described the condition of the electron when E1
Ground state
What causes the electron to leave E1 level
Acquires energy or is heated
Why does the electron not stay in E2 E3 etc
Higher energy states unstable
What is the energy level that produces colour
N= 2
How does modern atomic theory describe behaviour of electrons
Electrons are tiny particles that also have wave properties
What was the purpose of milikans oil drop experiment
Measure magnitude of charge of electron
What happens in a radioactive nucleus during beta decay
Neutron changes into a proton and an electron which is emitted
Why does ammonia have hydrogen bonding
Nitrogen small and highly electronegative
Why does ammonia have highest boiling point
It has hydrogen bonding which is stronger than the other intermolecular forces
Why is phosphine’s boiling point lower than arsine
Phosphine molecules smaller
