CCEA A-Level Chemistry AS 1 Basic Concepts overview quiz quiz

Charge 0, mass 1

Charge +1, mass 1

Charge -1, mass negligible

Charge 0, mass negligible

By simply taking the mass of the single most abundant isotope present in the sample

By taking the weighted mean of the isotope masses using their abundances

By adding together all the separate isotope masses shown on the spectrum

By dividing the largest isotope mass by the smallest isotope mass

n = m x M

n = RT/pV

n = pV/RT

n = c/V

Trigonal planar, 120 degrees

Pyramidal, 107 degrees

Bent, 104.5 degrees

Tetrahedral, 109.5 degrees

Van der Waals (London) forces

Hydrogen bonding

Permanent dipole-dipole forces

Ionic forces

+2

+4

+6

+7

It loses electrons to another species and is itself oxidised

It gains electrons and is itself reduced

It is not chemically changed at all during the reaction

It must always contain oxygen within its structure

The reaction is endothermic, so delta H is positive

There is no enthalpy change

The reaction is exothermic, so delta H is negative

delta H equals q exactly

bonds broken minus bonds formed

bonds formed minus bonds broken

bonds broken plus bonds formed

bonds formed divided by bonds broken

The curve shifts to the left and the height of its peak rises sharply

The curve shifts right and flattens, increasing the area beyond Ea

The total area enclosed underneath the whole curve increases noticeably

The activation energy itself moves across to a much lower value on the axis

It shifts the position of equilibrium across towards the products

It shifts the position of equilibrium back towards the reactants

It has no effect on the position, only on the rate

It increases the value of the equilibrium constant Kc

Increase the yield of product

Have no effect on the yield

Change the products formed

Decrease the yield of product