Category: Chemistry

4.89g of potassium hydroxide was dissolved in deionised water and made up to 250cm³ in a volumetric flask.

20.0cm³ samples were titrated against hydrochloric acid solution of concentraion 0.300 mol dm^-3.

A mean titre of 18.85cm³ of hydrochloric acid solution was obtained.

Calculate the percentage purity, by mass, of the original solid. (Don't include the % symbol and give answer to 1 decimal place!)

2.82g of lithium carbonate was dissolved in deionised water and made up to 250cm³ in a volumetric flask.

10.0cm³ samples were titrated against hydrochloric acid solution of concentraion 0.100 mol dm^-3.

A mean titre of 28.70cm³ of hydrochloric acid solution was obtained.

Calculate the percentage purity, by mass, of the original solid. (Don't include the % symbol and give answer to 1 decimal place!)

0.925g of lithium hydroxide was dissolved in deionised water and made up to 250cm³ in a volumetric flask.

25.0cm³ samples were titrated against sulfuric acid solution of concentraion 0.100 mol dm^-3.

A mean titre of 13.75cm³ of sulfuric acid solution was obtained.

Calculate the percentage purity, by mass, of the original solid. (Don't include the % symbol and give answer to 1 decimal place!)

2.49g of potassium hydroxide was dissolved in deionised water and made up to 250cm³ in a volumetric flask.

20.0cm³ samples were titrated against hydrochloric acid solution of concentraion 0.150 mol dm^-3.

A mean titre of 21.90cm³ of hydrochloric acid solution was obtained.

Calculate the percentage purity, by mass, of the original solid. (Don't include the % symbol and give answer to 1 decimal place!)

1.56g of lithium hydroxide was dissolved in deionised water and made up to 250cm³ in a volumetric flask.

25.0cm³ samples were titrated against sulfuric acid solution of concentraion 0.100 mol dm^-3.

A mean titre of 23.20cm³ of sulfuric acid solution was obtained.

Calculate the percentage purity, by mass, of the original solid. (Don't include the % symbol and give answer to 1 decimal place!)

By titration, it was found that an average titre of 9.90cm³ of 1.00 mol dm^-3 solution of potassium carbonate was required to just neutralise a 25.00 cm³ sample of sulfuric acid solution. Calculate the concentraion of the sulfuric acid solution.

The equation for the reaction is

K₂CO_3(aq)+H₂SO_4(aq)=>K₂SO_4(aq)+H₂O_(aq)+CO_2(g)

By titration, it was found that an average titre of 21.30cm³ of 0.100 mol dm^-3 solution of sulfuric acid was required to just neutralise a 25.00 cm³ sample of potassium hydroxide solution. Calculate the concentraion of the potassium hydroxide solution.

The equation for the reaction is

2KOH_(aq)+H₂SO_4(aq)=>K₂SO_4(aq)+H₂O_(aq)

By titration, it was found that an average titre of 20.00cm³ of 0.150 mol dm^-3 solution of hydrochloric acid was required to just neutralise a 10.00 cm³ sample of sodium hydroxide solution. Calculate the concentraion of the sodium hydroxide solution.

The equation for the reaction is

NaOH_(aq)+HCl_(aq)=>NaCl_(aq)+H₂O_(aq)

By titration, it was found that an average titre of 19.10cm³ of 0.250 mol dm^-3 solution of sulfuric acid was required to just neutralise a 10.00 cm³ sample of potassium hydroxide solution. Calculate the concentraion of the potassium hydroxide solution.

The equation for the reaction is

2KOH_(aq)+H₂SO_4(aq)=>K₂SO_4(aq)+H₂O_(aq)

By titration, it was found that an average titre of 22.25cm³ of 0.100 mol dm^-3 solution of hydrochloric acid was required to just neutralise a 20.00 cm³ sample of lithium hydroxide solution. Calculate the concentraion of the lithium hydroxide solution.

The equation for the reaction is

LiOH_(aq)+HCl_(aq)=>LiCl_(aq)+H₂O_(aq)

What volume (in cm³) of deionised water would you need to add to 200cm³ of nitric acid to dilute it from a concentration of 4.00 mol dm^-3 into a concentration of 1.00 mol dm^-3?

Calculate the concentration of potassium hydrogencarbonate in a solution of volume 425cm³ that contains 75.0 g of potassium hydrogencarbonate

K=39.1 H=1.0 C=12.0 O=16.0

Calculate the concentration of iodine in a solution of volume 2.40dm³ that contains 100 g of iodine

I=126.9

Calculate the concentration of barium nitrate in a solution of volume 21.95cm³ that contains 0.670 g of barium nitrate

Ba=137.3 N=14.0 O=16.0

Calculate the concentration of iodine in a solution of volume 1.20dm³ that contains 100 g of iodine

I=126.9

Calculate the volume of solution in cm³ that would contain 5.00 mol of glucose if the concentration of the solution is 2.50 mol cm^-3

Calculate the volume of solution in dm³ that would contain 0.100 mol of KI if the concentration of the solution is 0.125 mol dm^-3

Calculate the number of moles of sulfuric acid in a solution of volume 10.00 dm³ and a concentration of 0.240 mol dm^-3

Calculate the number of moles of nitric acid in a solution of volume 500.00 cm³ and a concentration of 6.00 mol dm^-3

Calculate the number of moles of hydrochloric acid in a solution of volume 19.50 cm³ and a concentration of 0.250 mol dm^-3

Calculate the temperature of a sample of nitrogen (in ^oC) if 0.118 mol of nitrogen has a volume of 1700cm³ and is at a pressure of 192kPa

Calculate the temperature of a sample of water vapour (in K) if 0.180 mol of water vapour has a volume of 3000cm³ and is at a pressure of 250kPa

Calculate the temperature of a sample of carbon dioxide (in K) if 0.500 mol of carbon dioxide has a volume of 17.8dm³ and is at a pressure of 50000Pa

Calculate the temperature of a sample of hydrogen (in K) if 1.00 mol of hydrogen has a volume of 24.0dm³ and is at a pressure of 101000Pa

Calculate the number of moles of gas present at r.t.p in 20.0 dm³ of ethene.

Calculate the number of moles of gas present at r.t.p in 40.0 dm³ of hydrogen chloride.

Calculate the number of moles of gas present at r.t.p in 590 cm³ of fluorine.

Calculate the number of moles of gas present at r.t.p in 52.0 dm³ of carbon dioxide.

0.257g of gas was collected. The volume of gas was recored as 190 cm³ at a temperature of 270 K and a pressure of 95000Pa

Determine the relative formula mass of the chemical.

0.438g of volatile liquid was vaporised and the gas collected. The volume of gas was recorded as 286 cm³ at a temperature of 358 K and a pressure of 120000Pa

Determine the relative formula mass of the chemical.

Calculate the number of moles of potassium hydrogen carbonate if you have 9.00 g of potassium hydrogen carbonate

K=39.1 H=1.0 C=12.0 O=16.0

Calculate the number of moles of white phosphorous (P₄) if you have 12.4 g of white phosphorous (P₄)

P=31.0

Calculate the number of moles of NH₄NO₃ if you have 32.0 g of NH₄NO₃

N=14.0 O=16.0 H=1.0

Calculate the mass of propene that you would have if you had 0.0500 mol of propene

C=12.0 H=1.0

Calculate the mass of phosphorus (V) oxide (P₄O₁₀) that you would have if you had 1.25 mol of phosphorus (V) oxide (P₄O₁₀)

P=31.0 O=16.0

Calculate the mass of ammonium nitrate that you would have if you had 0.500 mol of ammonium nitrate

N=14.0 O=16.0 H=1.0

Calculate the mass of nitrogen that you would have if you had 6.00 mol of nitrogen

N=14.0

Calculate the mass of P₂O₅ that you would have if you had 0.100 mol of P₂O₅

P=31.0 O=16.0

Calculate the mass of CuSO₄ . 5H₂O that you would have if you had 1.9 mol of CuSO₄ . 5H₂O

S=32.1 Cu=63.5.0 O=16.0 H=1.0

Calculate the mass of H₂S that you would have if you had 6.00 mol of H₂S

S=32.1 H=1.0

Potassium hydroxide will neutralise nitric acid according to the equation

KOH+ HNO₃=>KNO₃+ H₂O

What volume of 4mol dm^-3 HNO₃ will neutralise 80 cm³ of 1mol dm^-3 KOH?

Zinc metal reacts with hydrochloric acid

Zn+ 2HCl=>ZnCl₂+H₂

What volume of H₂ (measured at r.t.p.) would be produced by reaction of 1 litre of 0.5 mol dm^-3 HCl with an excess of zinc?

[1] ½ dm³

[2] 6 dm³

[3] 12 dm³

[4] 24 dm³

What mass of KOH is contained in 100cm³ of 5mol dm^-3 KOH solution?

What is the mass of 24.0 dm³ of hydrogen sulphide if all volumes are measured at r.t.p?

What is the volume (in dm³) at room temperature and pressure of 1.00g of neon?

How many moles of NO₂ can be made by full decomposition of 1 mole of Pb(NO₃)₂ if the equation for this reaction is:

2Pb(NO₃)₂ => 2PbO + 4NO₂ + O₂

Ca₃N₂

BaCO₃

sulfur (VI) fluoride

Calculate the mass of 0.100 mol of lead atoms

If the paracetamol molecule shown below is hydrolysed in hot dilute hydrochloric acid, what are the main organic products?

The main forces which hold a coiled protein chain into an alpha-helix are:

Which of these amino acids are chiral?

(i) CH₃CHNH₂CO₂H

(ii) C₆H₅CH₂CHNH₂CO₂H

(iii) HOCH₂CHNH₂CO₂H

(iv) CH₂NH₂CO₂H

Step 7:

Which of these reagents are nucleophiles?

(i) Br₂

(ii) NH₃

(iii) NO₂⁺

(iv) CN^-

Consider the following reaction:

NO_2(g) + CO_(g) => NO_(g)+ CO_2(g)

The rate equation was found, by experiment:

rate = k [NO₂]²

Which of the following statements is/are true?

(i) The mechanism has more than one step

(ii) CO is involved in the rate determining step

(iii) NO₂ is produced in one of the steps

(iv) The mechanism has only one step

K_p = 4 atm for the dissociation of N₂O₄ at 350 K when the equilibrium is described by this equation.

N₂O_4(g) <=> 2NO_2(g)

What is the value of K_p for this equilibrium:

2NO_2(g) <=> N₂O_4(g)?

The indicator thymol blue changes from yellow to blue of the pH range 8.0 to 9.6. The indicator could be used to detect accurately the end-point in a titration of roughly 0.1 mol dm^-3 solutions of:

(i) ethanoic acid with sodium hydroxide

(ii) hydrochloric acid with ammonia

(iii) hydrochloric acid with sodium hydroxide

(iv) ethanoic acid with ammonia

When four bromide ions combine with a cobalt(II) ion

(i) the charge on the complex ion is 2-

(ii) the shape of the complex ion is tetrahedral

(iii) the coordination number of the cobalt atom is 4

(iv) the name of the complex is the tetrabromocobalt (II) ion

What is the value of E^ϴcell/V observed for a cell constructed from the following half-cells. (These are the half-cells that are put together in a car battery (6 cells in series)?

PbSO_4(s) + 2e^- <=> Pb_(s) + SO₄^2-_(aq) E^ϴ/V = -0.36

PbO_2(s) + SO₄^2-_(aq)+4H_(aq) + 2e^- <=> PbSO_4(s) + 2H₂O(l) E^ϴ/V = +1.69

For this question, look at the resource, ‘A Selection of Standard Electrode Potentials’ (‘A Selection of Standard Electrode Potentials’can be found in TOOLS>Data Sheets)

Which chemical species is most resistant to reduction?

Work out the ratio of the species in the following half-equation.

I₂ + e^- => I^-

I₂ = [1] 1 [2] 2 [3] 3 [4] 4 [5] 5 [6] 6

e^- = [7] 1 [8] 2 [9] 3 [10] 4 [11] 5 [12] 6

I^- = [13] 1 [14] 2 [15] 3 [16] 4 [17] 5 [18] 6

Work out the ratio of the species in the following half-equation.

Cu => Cu²⁺ + e^-

Using oxidation numbers (states) work out the ratio of the species in the following half-equation.

S₂O₃^2- => S₄O₆^2- + e^-

Which of these complex ions have a colour in solution?

(i) [Sc(H₂O)₃]²⁺

(ii) [CuCl₂]^-

(iii) [Zn(OH)₄]^2-

(iv) [Co(H₂O)₆]²⁺

Which of the following can act as a bidentate ligand in the formation of complexes with metal ions?

(i) S₂O₃^2-

(ii) C₂O₄^2-

(iii) SCN^-

(iv) H₂NCH₂CH₂NH₂

Calculate the value of the enthalpy change associated with the following equation?

2Cl_2(g)=> 4Cl_(g)

The magnitude (numerical value) of the lattice enthalpy for these compounds increase from left to right putting first the compound with the least negative value?

(i) LiCl - LiBr - LiI

(ii) MgO - BaO - BaS

(iii) NaCl - KCl - RbCl

(iv) NaF - MgF₂ - AlF₃

Consider the following equilibrium:

N_2(g) + O_2(g) <=>2NO_(g)

5.00 x 10^-3 mol of N₂ was mixed with 4.00 x 10^-3 mol of O₂ and 11.0 x 10^-3 mol of NO and the mixture sealed in a container. The volume of the container was 0.500 dm³. The mixture was left to form a stable equilibrium. At this point, 9.00 x 10^-3 mol of NO was present in the mixture. The pressure was recorded as 45000 kpa

Calculate the value of K_p (no units) under these conditions.

Consider the following equilibrium:

2SO_2(g) + O_2(g) <=>2SO_3(g)

8.00 mol of SO₂ was mixed with 5.00 mol of O₂ and the mixture sealed in a heated vessel of volume of 1.00 dm³. The mixture was left until no further observable change in composition took place. At this point, 2.00 mol of O₂ was present in the mixture and the pressure was recorded as 200 kPa.

Calculate the value K_c (in units: mol^-1 dm³) under these conditions.

When ethene reacts with bromine in the presence of aqueous sodium chloride the organic products include:

(i) CH₂BrCH₂Br

(ii) CH₂BrCH₂Cl

(iii) CH₂ClCH₂Br

(iv) CH₂ClCH₂Cl

Which of these reagents are nucleophiles?

(i) Br₂

(ii) NH₃

(iii) NO₂⁺

(iv) CN^-

Which of these chemical species are nucleophiles with react with halogenoalkanes?

(i) cyanide ions

(ii) hydroxide ions

(iii) ammonia molecules

(iv) ammonium ions

Which of these changes represents a termination step of a chain reaction?

(i) CH₃^. + CH₃^. -> CH₃CH₃

(ii) CH₃^. + Br₂ -> CH₃Br + Br^.

(iii) Br^. + Br^. -> Br₂

(iv) Br^. + CH₄ -> CH₃^. + HBr

Step 6:

Which of these polymers would you expect to have the strongest intermolecular (interchain) forces as a result of the presence of polar covalent bonds?

What is the systematic name of the following molecule?

CH₃CH₂CH₂C(NH₂)CHCH₃

Heating methylbenzene under reflux with excess, alkaline potassium manganate(VII) which is a strong oxidising agent produces:

Which types of change are involved in this sequence of changes (but not necessarily in the order listed)?

CH₃CH₂CH₂OH -> CH₃CH₂CHO -> CH₃CH₂CO₂H -> CH₃CH₂CO₂CH₂CH₃

(i) hydrolysis

(ii) esterification

(iii) acid-base

(iv) oxidation

Which reagent converts butan-2-one to butan-2-ol?

An alkane in petrol is:

Products formed by heating 2-bromo-3-methylbutane with a solution of potassium hydroxide in ethanol (an elimination reaction) include:

(i) 2-methylbut-1-ene

(ii) 3-methylbut-2-ene

(iii) 2-methylbut-3-ene

(iv) 3-methylbut-1-ene

Choose one of the following options:

Choose one of the following options:

What is the oxidation number of SULFUR in

SO₄^2-

What is the oxidation number of NITROGEN in

NaNH₂

Iodine oxidises thiosulfate ions, S₂O₃^2 -, to S₄O₆^2- . What is the oxidation number (O.N.) change for each sulfur atom?

How many complete shells are there in the zinc atom?

Which of these compounds is an acid?

Which of these conversions are reductions?

(i) CrO₄^2- to Cr₂O₇^2-

(ii) CrO₄^2- to Cr³⁺

(iii) CrO₄^2- to CrO₃

(iv) CrO₃ to Cr₂O₃

Which of these processes are endothermic?

(i) water freezing

(ii) ethanol evaporating

(iii) steam condensing

(iv) wax melting

What is/are the bond angle(s) found in iodine trifluoride?

(i) 104.5^o

(ii) 120^o

(iii) 107^o

(iv) 90^o

What is/are the bond angle(s) found in PCl₅?

(i) 90^o

(ii) 104.5^o

(iii) 120^o

(iv) 180^o

What is the bond angle found in BF₃?

What is the bond angle found in water?

Which of these sets of properties is that of a substance which is molecular?

How many chloride ions touch each sodium ion in the crystal structure of sodium chloride?

Which of these materials consist of a giant structure of ions?

(i) magnesium oxide

(ii) silicon dioxide

(iii) potassium fluoride

(iv) silicon chloride

How many partially filled orbitals are there in the nitrogen atom?

For which of these equilibria does a change in pressure have no effect on the yield of substances on the right-hand side of the equation?

(i) CH_4(g) + H₂O_(g) <=> 3H_2(g) + CO_(g)

(ii) 2HI_(g) <=> H_2(g) + I_2(g)

(iii) 2SO_2(g) + O_2(g) <=> 2SO_3(g)

(iv) H₂O_(g) + CO_(g) <=> H_2(g) + CO_2(g)

Which of these reactions can be reversed by changing the conditions in a typical advanced chemistry laboratory?

(i) CuSO₄.5H₂O_(s) -> CuSO_4(s) + 5H₂O(l)

(ii) 2Mg_(s) + O_2(g) -> 2MgO_(s)

(iii) NH_3(g) + HCl_(g) -> NH₄Cl_(s)

(iv) CH_4(g) + 2O_2(g) -> CO_2(g) + 2H₂O_(l)

The value that you obtain for the enthalpy of combustion Δ_cH of liquid ethanol using mean bond enthalpies is different from the value obtained experimentally, or by using enthalpy of formation Δ_fH of liquid ethanol.

What is the most significant reason for this?

Chlorine disproportionates when it reacts with:

In which of these molecules do the intermolecular forces arise largely from attractions between temporary dipoles?

Which of the following increase from left to right along the series Mg - Ca - Sr - Ba?

(i) the thermal stability of the nitrates

(ii) the thermal stability of the carbonates

(iii) the solubility of the hydroxides in water

(iv) the solubility of the sulfates in water

What is the oxidation number of CARBON in methanal

CH₂O

What is the oxidation number of OSMIUM in

OsO₄

What is the oxidation number of SULFUR in

SO₃

Which of these statements about atomic and ionic radii are true?

(i) Atomic radii increase down group 2

(ii) Ionic radii increase down group 7

(iii) Atomic radii decrease across period 3

(iv) In period 3 the ionic radii are smaller than the atomic radii

Choose one of the following options:

Which of the following statements describe molecules that are stereo isomers?

(i) molecules whose atoms have a different arrangement in space

(ii) molecules that have the same molecular formula

(iii) molecules in which the atoms are joined to the same neighouring atoms

(iv) molecules which the same atoms but the atoms are bonded in a different order

A compound X with the molecular formula C₄H₁₀O has a broad peak in its IR spectrum at 3500cm^-1.

Oxidation of X with excess potassium dichromate(VI) gives a product Y which is not an acid and does not reduce Fehling's solution.

Y has a strong peak in its IR spectrum at 1700cm^-1.

Identify X and Y. (See also the data in question 9.)

The mass spectrum of chlorine includes three peaks at mass-to-charge ratios of 70, 72 and 74.

The order of the heights of these peaks is:

Heating butan-1-ol with a mixture of sodium bromide and concentrated sulfuric acid produces 1-bromobutane. During the preparation the reaction mixture turns orange due to the formation of:

Which reagent can be used to convert butan-1-ol to but-1-ene?

Why is ethanol a liquid while propane is a gas? (Relative atomic masses: C = 12, H = 1, O = 16)

Which of these alkenes will produce the largest %yield of 2-bromopentane when it is reacted with hydrogen bromide?

How many monosubstitution products can be formed when butane reacts with chlorine?

One mole of an alkane needs 8 moles of oxygen for complete combustion. What is the molecular formula of the alkane?

The members of the homologous series of alkanes:

(i) are all straight-chain compounds

(ii) have the general formula C_nH_(2n + 2)

(iii) have identical chemical properties

(iv) show a regular gradation of physical properties as the number of carbon atoms increases.

The mass spectrum of copper has two significant peaks. The peak at 63 has a relative abundance of 69 and the peak at 65 has a relative abundance of 31.

This shows that the relative atomic mass of copper is:

How many functional group isomers of C₄H₈ are there?

What is the oxidation number of NITROGEN in

NaNH₂

What is the oxidation number of CARBON in

CCl₄

Which of these comparative statements are true?

(i) a calcium atom is larger than a calcium ion

(ii) a calcium atom has a larger radius than a magnesium atom

(iii) calcium has a smaller first ionisation energy than magnesium

(iv) a calcium ion is smaller than a magnesium ion

Using enthalpies of formation Δ_fH, calculate the enthalpy change for the following esterification reaction.

CH₃COOH_(l) + C₂H₅OH_(l) => CH₃COOCH₂CH_3(l) + H₂O_(l)

Select the data from the 'Selection of Enthalpies of Formation and Combustion' shown above.

If this question was generated from Random Retrieval, this data can also be found in TOOLS>Data Sheets.

How many complete sub-shells are there in the phosphorus atom?

What is the bond angle found in BF₃?

The reaction of propanone with HCN in the presence of some KCN is an example of:

Ethyl ethanoate is heated under reflux with excess aqueous sodium hydroxide. The resulting solution is distilled. The distillate contains:

The reaction of benzene with ethanoyl chloride in the presence of aluminium chloride

(i) involves CH₃-CO⁺ as an intermediate

(ii) forms C₆H₅-CO-CH₃

(iii) is a substitution reaction

(iv) involves nucleophilic attack on benzene

What value should go in the blank box in the table?

Consider the following reaction:

2H₂O_2(g) => 2H₂O_(g)+ O_2(g)

The rate equation was found, by experiment:

rate = k [H₂O₂]

Which of the following statements is/are true?

(i) The mechanism must be multi step

(ii) Doubling [H₂O_{] quadruples the rate of the reaction}

(iii) [H₂O] must be consumed in more than one step

(iv) The mechanism probably has only one step

Consider the following equilibrium for the Haber-Bosch process:

3H_2(g) + N_2(g) <=>2NH_3(g)

32.0 mol of H₂ was combined with 12.0 mol of N₂ and the mixture sealed and pressurised in a vessel of volume 2.00 dm³. The mixture was left until no further observable change in composition took place. At this point, 4.00 mol of NH₃ was found to be present in the mixture. The pressure was recorded as 200 000 kPa.

Calculate the value of K_c (in units: mol^-2 dm⁶) under these conditions.

From your calculation of ΔG in question 3, decide whether a solid dry sample of NaHCO_3(s) will decompose or will be thermally stable in the oven at 100^oC.

If this question is from a Random Retrieval, you can also carry out this calculation of Gibbs Energy change, ΔG, by first working out values for ΔS^Ɵ and ΔH^Ɵ by selecting the appropriate data from the ‘Selection of Thermodynamic Data’ in TOOLS.

Which of the first-row d-block metals forms aqueous ions which are mauve in the +2 state, green in the +3 state, blue in the +4 state and yellow in the +5 state?

Which of these complex ions have a colour in solution?

(i) [Sc(H₂O)₃]²⁺

(ii) [CuCl₂]^-

(iii) [Zn(OH)₄]^2-

(iv) [Co(H₂O)₆]²⁺

Work out the ratio of the species in the following half-equation.

S₂O₃^2- => S₄O₆^2- + e^-

Which of these compounds is an acid?

In which of these elements are the atoms or molecules closely packed but free to move around sliding past each other at room temperature?

(i) mercury

(ii) argon

(iii) bromine

(iv) iodine

Which of these statements is true of a metallic crystal?

(i) It consists of atoms strongly held together by metallic bonding.

(ii) It consists of a regular array of positive ions in a sea of negative electrons.

(iii) The crystal is held together by the attraction between positive metal ions and electrons.

(iv) The crystal is negatively charged.

Zinc conducts electricity at room temperature because:

(i) the metal is solid

(ii) zinc is a d-block element

(iii) the atoms in the structure are in contact with each other

(iv) the bonding electrons are delocalised

Typically metal elements, unlike most solid non-metal elements:

(i) are shiny

(ii) conduct electricity

(iii) bend and stretch without breaking

(iv) have low tensile strength.

In which of these molecules do the intermolecular forces arise largely from hydrogen bonding?

What is the bond angle found in SF₆?

What is the bond angle found in methane?

An element M has two electrons in its outer shell. An element X has seven electrons in its outer shell. What is the likely formula of the compound of X and Y?

How many sulfate ions are there in 0.01 mol aluminium sulfate?

(The Avogadro constant = 6.02 x 10²³ mol^-1)