Zadanie 2a
Iodine crystals, I2(s), were sealed in a flask and left until an equilibrium was reached with violet vapour above the crystals. I2(s) ⇌ I2(g) (i) Name the change of state from I2(s) to I2(g) and state the type of force between…
Types of intermolecular forces
Deduce which intermolecular forces (London dispersion, dipole-induced dipole, dipole-dipole, hydrogen bonding) act between given molecules from their size, polarity and the presence of hydrogen bonded to nitrogen, oxygen or fluorine.
Tę umiejętność sprawdzają 32 zadania wzorowane na arkuszach IB z lat 2022–2026.
Zadania sprawdzające tę umiejętność: 32 Otwórz w wyszukiwarce z filtrami
Zadanie 2a
The structure of lycopene is shown. To separate the lycopene, the filtered juice was shaken in a separating funnel with heptane, C7H16, and the mixture was left to form two immiscible layers, which were run into separate flasks. Predict which layer will…
- Materiał graficzny
Zadanie 4c
The compounds butan-1-ol and ethoxyethane have the same molar mass. Their structures are shown below. Explain, with reasons, why butan-1-ol has a higher boiling point than ethoxyethane.
- Materiał graficzny
Zadanie 8
The three isomers of C4H8O in the table have the same molar mass. What is the reason for the increase in boiling points? A. Increase in the number of covalent bonds per molecule B. Increase in molar mass C. Increase in the strength of intermolecular…
- Tabela do uzupełnienia
Zadanie 7c
Nitric acid can form hydrogen bonds with water. Annotate the structures below to show the formation of a hydrogen bond between a molecule of nitric acid and a molecule of water. Use a dotted line to represent the hydrogen bond.
- Materiał graficzny
Zadanie 7d
Discuss the melting points in the table below in terms of the bonding and/or intermolecular forces present in each substance.
- Tabela do uzupełnienia
Zadanie 8
Hydrogen fluoride boils at 20 °C, whereas hydrogen chloride boils at −85 °C. Which type of intermolecular force accounts for the much higher boiling point of hydrogen fluoride? A. Hydrogen bonding B. Dipole-dipole forces C. London (dispersion) forces D.…
Zadanie 1b
4.81 g of sulfur was heated in a stream of chlorine gas until the reaction was complete. The mass of the chloride produced was 10.13 g. (i) Calculate how many atoms are present in this 4.81 g sample of sulfur. Use sections 2 and 7 of the data booklet. (ii)…
Zadanie 3d
Deduce, giving a reason, which of the two dyes, orange or violet, is the more polar.
- Materiał graficzny
Zadanie 5c
(i) Deduce the condensed electron configuration of chlorine. (ii) Describe the bonding in a molecule of chlorine in terms of valence electrons. (iii) Explain why chlorine has a much lower boiling point than bromine, although both exist as simple diatomic…
- Materiał graficzny
Zadanie 8
Which substance has dipole-dipole forces between its molecules? A. CO2 B. Cl2 C. CH4 D. CH3Cl
Zadanie 14
Which of these alkanes boils at the lowest temperature? A. CH3CH2CH2CH2CH3 B. C(CH3)4 C. (CH3)2CHCH2CH3 D. CH3CH2CH2CH2CH2CH3
Zadanie 5b
The graph shows the boiling points of five straight-chain carboxylic acids and of the five methyl esters that have the same relative formula masses as the acids. (i) Outline why the carboxylic acids have higher boiling points than the esters with the same…
- Materiał graficzny
Zadanie 4b
Butane, C4H10, and propenal have similar molar masses, yet propenal is the less volatile. Compare and contrast the intermolecular forces in the two substances to account for this difference.
Zadanie 9
Citric acid gives lemon juice its sharp taste. It dissolves very readily in water. Its structure is shown. Explain why citric acid is soluble in water, with reference to its structure.
- Materiał graficzny
Zadanie 12
Which pair of liquids is immiscible? A. CH3OH and CH3CH2CH2OH B. CH3COCH3 and H2O C. C6H14 and CCl4 D. C6H12 and H2O
Zadanie 17b
Paracetamol and phenacetin are two analgesics with similar structures. Predict, giving a reason, which of the two compounds is more soluble in water.
- Materiał graficzny
Zadanie 1a
The graph shows the boiling points of the straight-chain alkenes with a terminal double bond, from ethene to hex-1-ene. (i) Explain why the boiling point rises from ethene to but-1-ene. (ii) A sample of but-1-ene is warmed from 250 K to 300 K at constant…
- Materiał graficzny
Zadanie 1a
Young mussels were placed in a contaminated harbour. Samples were taken at regular intervals and the tin content of the soft tissue was determined. (i) The tin content follows a linear trend during the first six weeks. Deduce the equation for this part of the…
- Materiał graficzny
Zadanie 10
Which row correctly states the types of intermolecular force present between molecules of ethane, methylamine and fluoromethane? A. Ethane: London (dispersion) forces only; methylamine: London forces, dipole-dipole forces and hydrogen bonding; fluoromethane:…
Zadanie 2c
(i) State the electron domain geometry of the water molecule. (ii) Deduce the Lewis (electron dot) structure of water and sketch its 3D molecular shape. (iii) Explain, with reference to the forces between molecules, why water has a higher boiling point than…
Zadanie 9
Which compound is both volatile and soluble in water? A. C6H14 B. KBr C. SiO2 D. CH3CH2OH
Zadanie 1d
Ethanoic acid and propanone, CH3COCH3, each contain a C=O group, and their molar masses are close. (i) Considering the strongest intermolecular forces in each liquid, explain why propanone boils at a much lower temperature than ethanoic acid.…
Zadanie 1d
Ethanoic acid and propanone, CH3COCH3, both contain a carbonyl group and have similar molar masses. (i) Explain, in terms of the strongest intermolecular forces present in each liquid, why propanone boils at a much lower temperature than ethanoic acid.…
Zadanie 3b
The properties of a material depend on the way its atoms are bonded and arranged. Sheets of pyrolytic graphite, which consists of many stacked layers of carbon atoms, are used in some phones to spread heat away from the processor. A sheet conducts heat very…
Zadanie 6b
Palmitic acid, CH3(CH2)14COOH, and palmitoleic acid, CH3(CH2)5CH=CH(CH2)7COOH, which has a cis C=C double bond, both have a chain of sixteen carbon atoms. Predict which of the two fatty acids has the higher melting point and give two reasons for…
Zadanie 13
Which substance evaporates easily when pure and gives a strongly conducting solution in water? A. HBr B. KBr C. CH3Br D. NH3
Zadanie 3c
In one overall reaction, a carbonyl compound, Compound A, reacts with methylmagnesium iodide and the product is then treated with water: Compound A + CH3MgI + H2O → Compound B + Mg(OH)I (i) State the IUPAC name of Compound A. (ii) Identify…
- Materiał graficzny
Zadanie 4a
(i) Outline one way in which the bonding between carbon atoms in graphite differs from that in diamond. (ii) Explain why fullerene, C60, sublimes at a much lower temperature than graphite.
Zadanie 9
Which statement best describes the bonding between the atoms inside one molecule of ammonia, NH3? A. Hydrogen bonding between nitrogen and hydrogen atoms B. Each shared pair of electrons is attracted electrostatically to the nuclei of both bonded atoms…
Zadanie 12
What is the main attraction between molecules in liquid carbon tetrachloride, CCl4? A. Hydrogen bonding B. Ionic attraction C. Dipole–dipole forces D. London (dispersion) forces
Zadanie 4a
(i) Deduce the structural formula and the empirical formula of B. (ii) Explain, with reference to Le Châtelier’s principle, the effect on the yield of B of using dilute rather than concentrated sulfuric acid as the catalyst. (iii) Compound A has a lower molar…
- Materiał graficzny