End of Year Exam!! Flashcards

Question

TRANSITION STATE

Answer 1

- where original bond break and new ones form

Answer 2

- particles approach each other - repulsive forces between electron clouds slow them down - lost KE reappears as increased PE - activation energy higher when bonds of reactants are stronger

Answer 3

- minimum collision energy required to form transition state

Answer 4

- temperature is a measured of average KE

Answer 5

- raising concentration increases reaction rate - higher concentration of reacting particles cause and increase rate of collisions - doubling concentration, doubles reaction rate

Answer 6

- raise gas pressure (reduce vol/adding gas) creates greater concentration - increase in rate of collision between particles - double pressure, double reaction rate

Answer 7

- raising temperature means particles have greater KE - higher percentage of collisions have energy equal/greater than AE - greater % of collisions are successful

Answer 8

- heterogeneous reactions involve reactants in two separate phases (solid/solid, solid/liquid, liquid/gas) - can only collide at the surface boundary where phases make contact - increase SA exposes greater amount of reacting particles to a possible collision - increase rate of collisions

Answer 9

- substance that has the ability to speed up chemical reactions whilst remaining chemically unchanged at the end - transition metals Mn, Pt, Pd, Au, Rh - increase rate of reaction as provide alternative pathway with a lower AE - greater % of collisions will have equal/greater than AE - greater % being successful

Answer 10

- biological catalysts - very specific in reactions they catalyse - fast acting

Answer 11

- tendency of an atom to attract electrons - the ability of an atom in a molecule to attract electrons to itself - measured on a scale of 0-4 - higher electronegative = greater electron attraction

Answer 12

- 2 atoms of different EN forming of CB result in uneven sharing of electrons - electrons spend more time closer to more EN element - more electronegative element develops small negative charge (delta minus) - less electronegative element develops a small positive charge (delta positive) - bond dipole

Answer 13

- those with slight positive and slight negative charged ends - have net dipole - occurs in all molecules with a single bond dipole

Answer 14

- those where the bond dipoles are of equal size and act in symmetrically opposing directions where the dipoles cancel each other out - zero net dipole

Answer 15

- bonds that keep atoms clustered together within the molecule - strong

Answer 16

- bonds that keep molecules bonded to one another

Answer 17

- polar molecules able to attract one another due to weak electrostatic attraction between their dipoles - dipole dipole occurs between completely opposite charged ends of polar molecules - increase melting/boiling points - like dissolve in like

Answer 18

- all molecules - only intermolecular force present in non polar - weak for molecules with few electrons - show increasing strength for greater number in electrons - stronger in molecules whose shape allows max surface contact between molecules e.g. linear

Answer 19

- only occur in molecules with H-F, H-O, H-N - due to electrostatic attraction between lone pair and F, O, N, H covalently bonded to another F, O, N - melting and boiling points higher - are extremely soluble in other substances that can HB

Answer 20

- is a mixture where the particles of a solute are homogeneously spread amongst the particles of the solvent, major component of the mixture by mass - solubility of a solution is given as the mass that can dissolve in 100g of water

Answer 21

- solution contains less solute than it is able to dissolve

Answer 22

- solution contains as much solute as it normally can dissolve

Answer 23

- solution contains more solute than it can normally dissolve

Answer 24

- when these dissolve in water, they are entirely present as independent ions - strong acids

Answer 25

- when these dissolve in water, they are partly present as independent mobile ions but mostly as molecules - weak acids and bases

Answer 26

- when these dissolve in water, they do not produce independent mobile ions - entirely present as molecules

Answer 27

- depends on ability of positive ions to move freely towards negative electrode whilst negative ions move freely towards positive electrode - greater concentration of ions = greater ability to conduct current - strong electrolytes produce more conducting solution than weak electrolytes - non electrolytes produce non conducting solution

Answer 28

- occurs when an insoluble solid forms with a previously clear solution - happens when two ionic solutes combine to form an insoluble compound - then the insoluble compound will 'come ou' - forming a precipitate

Answer 29

- conduct electricity - blue litmus paper red - sour taste

Answer 30

- conduct an electric current - red litmus blue - bitter taste - soapy slippery feel

Answer 31

- bases dissociate realising OH- ions | - ions present in the ionic solid are released into water to form a solution of independent mobile ions

Answer 32

- acids ionise producing H+ ions | - molecules react with water to form ions not originally present within the substance

Answer 33

- acid base behaviour is centred on the ability of certain substances that contain H or OH to produce H+ or OH- when dissolved in water

Answer 34

- strong acids undergo COMPLETE ionisation | - weak acids undergo PARTIAL ionisation

Answer 35

- non metal oxides can be acids if combined with water first - resulting acids then ionise to form H+ ions and an acidic solution - metallic oxides can be basic if they dissociate when dissolved in water; releasing positive metal ions and oxide ions - oxide ions combine with water to produce hydroxide ions

Answer 36

- lab technique for separating and identifying the components, or solutes of a mixture of r a gas/liquid - type substances; mobile and stationary

Answer 37

- gas or liquid that transports the solution being tested through another substance e.g. water - movement within the mobile phase is controlled by the interactions with the mobile/or stationary phases - solubility and absorption will affect how fast/slow components move

Answer 38

- can be either a liquid or solid through which the tested substance is carried e.g. coffee filter paper or paper towel

Answer 39

- surface process in which there is an accumulation of a gas/liquid on a liquid/solid - based on the strength of the interaction between the adsorbent (acts as a substrate for the other chemicals to attach to) and the adsorbed molecules - two types; physiosorption and chemisorption

Answer 40

- involves the bulk properties e.g. the atoms and molecules of a solid/liquid/gas crossing the surface and entering the volume of the material - molecules are entirely dissolved or diffused in the absorbent and form a solution - difficult for them to be separated easily from the absorbent - two types; physical or chemical

Answer 41

- type of ADsorption | - Van der Waals interaction between substrate and adsorbate (the molecule that is adsorbed)

Answer 42

- type of ADsorption - involves more energy - chemical bonds (usually covalent) sticking the adsorbate to the adsorbent

Answer 43

- type of ABsorption - a non reactive process e.g. when oxygen in air dissolves in water - process depending upon the liquid and the gas, and on physical properties like solubility, temperature and pressure

Answer 44

- type of ABsorption - which takes place when the atoms or molecules are absorbed e.g. when hydrogen sulphide is removed from biogas streams and converted into sulphur as a solid

Answer 45

- Paper - Gas - Thin Layer (TLC) - High Performance Liquid (HPLC)

Answer 46

- stationary phase is PAPER - mobile phase can be aqueous (water-based) liquid or a non-aqueous organic (carbon based) solvent - separation technique used to separate and identify the components of a mixture - ink spots - polarity of components results in separation - highly polar absorb quicker - solvent front; solvent that travels furthest up the paper

Answer 47

- identifying individual substances in complex mixtures - mobile phase; chemically inert gas (helium) - stationary phase; non volatile viscous liquid with high boiling point which is dissolved in particles - particles packed into steel column or capillary column (hollow) - mixture inserted into carrier gas stream - chamber vaporises sample - flows into column, separation occurs - different tendencies to remain liquid or gas stream - retention time - put on graph

Answer 48

- time between injecting a sample and detecting the analyte

Answer 49

- the solvent or mobile phase in instrumental chromatography

Answer 50

- substance being analysed or separated

Answer 51

- improved form of column chromatography - solvent is forced through high pressures - much faster - allows for the use small particles, giving greater SA for interactions of phases - enables better separation - two types; normal and reversed

Answer 52

- column is filled with silica particles - solvent is non polar - polar compounds within mixture pass through will stick longer polar silica - non polar components pass through quicker

Answer 53

- column is the same - silica is made NON POLAR by attaching hydrocarbon chains - ensures strong attraction between the polar solvent and polar molecules in mixture - non polar compounds will force attractions with the hydrocarbons - polar molecules will travel fast through column

Answer 54

- solid liquid form of chromatography - stationary phase is a polar solvent - mobile phase is single solvent or combination - quick, simple - used to determine number of components in mixture, verify identity of components, progress of reaction

Answer 55

- a chemical that change colour as the concentration of hydrogen ions in a solution changes - used to determine the acidic or basic nature of a material over a range, and that the range is identified by change in indicator colour - litmus paper - universal indicator - phenolphthalein - methyl orange - bromothymol blue

Answer 56

- a dye extracted from various species of lichen that changes colour around the neutral range - neutral; green - acid; red - base; blue

Answer 57

- a synthetic indicator that changes colour in the basic range - slightly basic; colourless - highly basic; red

Answer 58

- a synthetic indicator that changes colour in the acidic range - highly acidic; red - slightly acidic; yellow

Answer 59

- a synthetic indicator than changes colour around the neutral range - slightly acidic; yellow - neutral; green - slightly basic; blue

Answer 60

- no volume - no attraction - never condense (due to no volume)

Answer 61

- gas have rapid, constant motion - no attractive force - no fixed volume - collide at high speed - collisions are elastic - KE and TEMP proportional

Answer 62

- atoms with the same number of protons, but differing numbers of neutrons - different forms of a single element

Answer 63

- Molecular compounds containing hydrogen and carbon - Natural Gas; mostly methane and ethane, small amounts of propane and butane - Petroleum; thousands of different hydrocarbons

Answer 64

1. longest continuous chain for STEM NAME 2. number the carbon atoms: type of bond (if double), halogen (F, Cl, Br, I), alkyl group (methyl, ethyl) 3. functional groups determines the suffix of stem name 4. prefixes ordered alphabetically, numbered according to atom, prefixes di, tri, tetra used if there are multiples of a group - numbers separated from letter with a dash, comma used to separate numbers

Answer 65

amount of substance used or produced --------------------------------------------------------- time taken

Answer 66

- valence shell electron pair repulsion theory | - molecular shape results from repulsion between groups of electrons

Answer 67

- linear - triangular Planar - tetrahedral - pyramidal - bent

Answer 68

- 1 or 2 groups of electrons | - - 180 angles

Answer 69

- 3 groups of electrons | - 120 angles

Answer 70

- 4 groups of electrons | - 109.5 angles

Answer 71

- 4 groups of electrons - 1 is a lone pair - Ideal; 109.5 - Actual; 107

Answer 72

- 4 groups of electrons - 2 are lone pairs - Ideal; 109.5 - Actual; 104.5

Answer 73

- angles that would give all the bonding and non bonding valence electrons the largest equal angle of separation

Answer 74

- slight pos/nega charged ends - net dipole - occurs in all molecules with a single bond - several bond dipoles can reinforce or cancel out each others effect (depend on strength and direction of individual dipoles) - able to attract one another due to weak electrostatic attraction DIPOLE DIPOLE FORCES - dissolve ionic solutes

Answer 75

- if bond dipoles are of equal size and act in symmetrically opposing directions they cancel out effects, making them have zero net dipole and non polar

Answer 76

- strong | - covalent bonds keeps atoms clustered together

Answer 77

- weak - forces between molecules keeps them bonded - easily overcome; melting, boiling, evaporating - covalent bonds between atoms not affected - only chemical changes affect bonds

Answer 78

- due to attract between dipole of polar molecule and ions charge - not a type of intermolecular force

Answer 79

- molecule with temporary dipole and induced dipole experience weak electrostatic attraction; dispersion forces - attractive forces are in a state of rapid change as the temporary and induced dipoles constantly form, rapidly disappear and reform elsewhere

Answer 80

- tendency of a substance to evaporate and is measured in kPA - weak intermolecular forces correspond to liquids that easily evaporate and have high vapor pressure - greater tendency to evaporate with increasing temperature - higher temperature = higher average molecular KE to enable molecules to escape their intermolecular forces of attraction

Answer 81

- properties of water are considered to be unique - consists of small particles with weak dispersion forces - strong polarity - strong capacity for hydrogen bonding - high melting and boiling point (O and 100) - because of the ability of water molecules to form hydrogen bonding with neighboring molecules that compensates for weak dispersion forces

Answer 82

- density in the solid phase is less than in the liquid phase - freezes it undergoes major expansion and density drops - reduced density of the solid explains why ice floats

Answer 83

- waters regular crystal lattice of ice that forms when water freezes - must allow for each water molecule to form 4 HYDROGEN BONDS with 4 neighbouring molecules - maximises hydrogen bonding but takes up space - liquid phase there is less hydrogen bonding

Answer 84

- liquids tendency to resist any increase in its surface area - stretchy surface skin appearance that wants to contract - causes water to form spherical droplets - allows certain insects to scamper across - result of strong intermolecular forces - imbalance of these forces causing surface molecules to be pulled inwards to the bulk of the liquid - surface is trying to contract and achieve a minimum area

Answer 85

- decrease L to R - due to increasing nuclear charge and electrons pulled closer to nucleus - increases down a group - as you go down the group the number of electron shells increases

Answer 86

- measure of how strongly an atom holds onto electron shells - increase L to R (atom wanting to hold electrons) - decreases down a group (atomic radius gets bigger, further distance between electron - weaker attraction)

Answer 87

- ability of an atom in a molecule to attract electrons to itself - increases L to R (atom wanting to gain electrons) - decrease down group

Brainscape's Knowledge GenomeTM

End of Year Exam!! Flashcards

Brainscape's Knowledge Genome^TM