Module 2 Flashcards
(19 cards)
Isotopes of an element
Atoms of the same element with different numbers of neutrons and different masses
An Ion
A positively or negatively charged atom or a (covalently bonded) group of atoms (a polyatomic ion), where the number of electrons is different from the number of protons.
Relative Isotopic Mass
The mass of an isotope compared with one-twelfth of the mass of an atom of carbon-12.
Relative Atomic Mass
The weighted mean mass of an atom of an element compared with one-twelfth of the mass of an atom of carbon-12.
Empirical formula
A formula that shows the simplest whole-number ratio of atoms of each element present in a compound.
Define an alkali
releases OH- ions into aqueous solution
Define a base
a substance which readily accepts H+ ions from an acid (proton acceptor)
What is meant by the term ionic bond
Electrostatic attraction between positive and negative ions
Explain what is meant by the term electronegativity
The ability of an atom to attract electrons (Electron pair) in a covalent bond
Describe what is meant by the term ionic lattice, in terms of the type and arrangement of particles present.
Repeating pattern of oppositely charged ions.
What is meant by the term covalent bond?
A shared pair of electrons.
What is a disproportionation reaction?
A reaction in which the same element is simultaneously oxidised and reduced.
Different isotopes of antimony have the same chemical properties. Explain why.
Same number of electrons in outer shell
How has a salt been formed in this reaction?
(Define salt)
A hydrogen ion of an acid has been replaced by a metal ion.
The student is not confident that their titre is accurate.
Suggest what the student should do next to reduce the effect of any random error in the titration.
Repeat titration until two titrations are concordant / agree within 0.1 cm3
Calculate mean titre from concordant titres.
What is meant by the term standard solution?
A solution of known concentration.
Describe the relative energies of the 2s orbital and each of the three 2p orbitals in a nitrogen atom
p-orbitals have greater energy than s-orbitals.
Three p-orbitals have equal energy.
State and explain two anomalous properties of ice caused by hydrogen bonding
Ice is less dense than water
The molecules in ice are held apart by hydrogen bonds OR ice has an open lattice/structure
Ice has a relatively high melting point
Hydrogen bonds are relatively strong OR Hydrogen bonds are stronger (than other intermolecular attractions or forces) OR More energy is needed to overcome hydrogen bonding.
SbCl3 molecules are polar.
Explain why.
There is a difference in electronegativities (between Sb and Cl) OR (Sb-Cl) bonds are polar OR have a dipole
The molecule is not symmetrical AND dipoles do not cancel.
