Addition Exam Prep Flashcards
Acid + Metal Hydroxide
Salt + water
Acid + Metal Oxide
Salt + water
Acid + Metal Carbonate
Salt + water + carbon dioxide
Acid + Metal hydrogen carbonate
Salt + water + carbon dioxide
Metal + acid
Salt + hydrogen
Metal + Oxygen
Metal Oxide
How can the strength of dispersion forces increase
Increase in size - strength increases as no. of electrons increases, resulting in increased strength of dispersion because net charges of dipoles.
Increase in surface area - increased branching of molecules results in increased surface area of interaction between molecules, hence stronger strength of dispersionb
Pure substances
Have a fixed/constant composition and well-defined and constant physical and chemical properties
Mixtures
Contain 2 or more different substances in varying ratios and can be separated using physical properties.
Homogenous
Uniform composition throughout
Heterogenous
Non uniform composition
Dilution
C1V1 = C2V2
Sieving
Separates components in a mixture based of particle size. Passed through sieve of suitable mesh to concentrate desired comppnent
Decantation
Decantation is the process of separation of liquid from solid and other immiscible (non-mixing) liquids, by removing the liquid layer at the top from the layer of solid or liquid below.
Uses density
Separating funnel
A separating funnel is used to separate two immiscible liquids based on their densities. The mixture is placed in the funnel, allowed to settle into two layers, and the denser liquid is drained off from the bottom. This method is commonly used to separate oil from water.
Explain the cathode ray tube
Applying an electric field across the cathode ray caused the ray to be deflected towards the positive pole proving that cathode rays were composed of negatively charged particles and that they have a high mass to charge ratio.
Rutherfords Gold Foil Experiment
Based on alpha particle scattering after striking a thin foil. This leads to the compulsion that most of the atom is empty space or space occupied by electrons, and that the nucleus is the source of mass.
Multiple lines in hydrogens emission spectrum.
Observed multiple spectral lines for hydrogen atom even though it has only one electron. The lines are due to the electrons making transition between energy levels. Certain orbits/ energy levels are available.
Chromatography
Series of analytical techniques used to separate mixtures of compounds for further use of analysis
Paper Chromatography
Stationary Phase - paper (polar)
Stationary Phase
Does not move, and compounds are attracted to it
Mobile Phase
More soluble compounds are carried faster as mobile phase moves
Adsorption
Slowing due to intermolecular forces w/ stationary phase
desorption
attraction to solvent stronger that attraction to stationary phases
TLC
stationary phase is polar silica gel.
Capillary action draws solvent up matrix –> dependent on solubility or charge, due to the interaction of solute and matrix.
Dry sample placed in matrix and solvent moves up and dissolves sample
Rf
da/ds
distance travelled by a/distance travelled by solvent
Advantages of TLC
Plate is rigid, therefore easier to controll
Reusable - scrape of gel, put in solvent, filter, reuse gel
Gas chromatography
mobile phase - intert gas under pressure
stationary phase - liquid
sample must by gaseous
HPLC
mp - liquid
sp - silica
Explain why water has high surface tension
Surface tension is the tendency of a liquid to resist any increase in its surface area. Water has high surface tension due to its strong intermolecular forces. At the water surface, there is an imbalance of forces causing surface molecules to be pulling inwards towards the bulk of the liquid. As a consequence the surface is trying to contract and achieve minimum surface area.
