States of Matter Flashcards
How does gas in surroundings effect drug
Is a molecular dispersion. Can effect storage and integrity of drugs
Measurement of solubility
Melting point. The higher the solubility the lower the melting point
Enthalpy Def.
Total kinetic energy of system
Entropy Def.
Order in shape and structure
When is a substance most stable
High entropy, low enthalpy
Differences between states of matter
intermolecular bonds, volume and shape
Plasma Def.
Ionizable gas
Solid and Liquid Classification
Condensed state = fixed volume
Gas and Plasma Classification
Free state = no condensed volume
Mesophase
Substance that shows both liquid and solid physical characteristics on molecular level. No fixed shape but can’t move like a liquid. 2 Types
Nematic Menophase
can move in the vertical plane but no others
Sematic Menophase
Can move in the horizontal plane but no others
Increase in heat energy in a substance is
Increase of kinetic energy in it’s particles
What is higher melting point linked to
Strong molecular bond and low solubility
What is increase in solubility linked to
Increase in temp (not thermodynamically stable) (not always)
Polarity in substance
water has high polarity (polar) , lipophillic substances have low polarity (non-polar, C and H)
Semi-solid
Liquid given a gelling agent (hydrocarbon). Agent forms mesh to trap liquid to stop it flowing free
How gas conc. is measured
Pressure
Evaporation Def.
Loss of liquid from top of water
How to stop gas from degrading drug
Specialised packaging eg thicker, fortified with certin materials
Boiling Def.
Loss of liquid throughout substance
Crystalline Form (def.)
Repeats of internal structure (patterns exist)
Amorphous Form (Def.)
Molecule arrangement with no pattern
Bonding in a Molecular Crystal
Solid H-bonding. Difficult to break (requires high energy)
Ionic Crystal Bonds
Ionic bonds. Water is highly efficient at separating (H+ for anions, OH- for cations)
Metal Crystal Bonds
Covalent. Not soluble in water
Covalent crystal bond
Covalent. Not soluble in water
Relationship between bond strength, solubility and melting point
Stronger bonds = lower solubility = higher melting/boiling point
How water breaks down a substance
Covalent: breaking substance bonds and forming bonds with substance. Ionic: H+ takes anions, OH- takes cations
What determines whether something is soluble in water
polarity
Relationship between vapour pressure and evaporation
The higher the vapour pressure = the higher propensity to evaporate
Vapour Def.
Gaseous substance form that concurrently exists as a liquid/solid (as it’s below critical temp)
Meter Dose Inhaler Mechanics
High vapour pressure. As actuator opens the gas in the metering valve expands out. This forms a vacumn pulling out liquid dosage form sending out a high velocity. This causes liquid to be disperesed as fine particles (correct size for lungs
Propellants Def. and examples
Liquid with a high vapour pressure Eg CFCs or hydrofluoroalkane
Vapour Applications
Fragrance (excipient), Decongestant or cough suppressor (therapeutic)
Aspirin Physical Desc
transparent/ white crystalline powder. Odourless, bitter tasting. Hydrolysed in moist air giving acetic acid smell
NaCl Physical Desc
Transparent/white crystalline powder. Salty taste. May contain CaCl2 or MgCl2 which absorb moisture
Ethanol Physical Desc.
Colourless, mobile, volatile liquid. Vinous odour
Ferrous \Sulphate Def.
Bluish-green monoclinic (parallelogram prism) crystals/granuels. Odourless witth metallic taste. Oxidises in moist air to foem brownish-yellow coat
Glucose Physical Desc.
White powder. Sweet taste. Water absorbant
Paracetamol Physical Desc
Colourless crystalline powder. Bitter taste
Caffeine Physical Desc
White powder/ glistening needles. Odourless, bitter taste
Diazepam Physical Desc
off-white - yellow crystalline powder. Odourless, initially tasteless, bitter after taste
Ibuprofen Physical Desc
Colourless, stable crystalline solid. Characteristic odour
Castor Oil Physical Desc
Pale yellow to transparent viscous, stable liquid. Tastes acrid with nauseating after taste. Stable unless excessively heated
White Soft Paraffin Physical Desc
Viscous, oily, translucent semisolid. Odourless and tasteless