AS-Level Chemistry: June 2018 Paper 1 PP Flashcards
State two differences between the ‘Plum Pudding’ Model and the Model of Atomic Structures used today.
(2 marks)
-Nucleus contains Protons and Neutrons.
-Electrons Orbit the Nucleus in Energy Levels/Shells/Orbitals.
Suggest how the procedure (Evaporation) could be improved, using the same apparatus, to give a more accurate value for x.
Justify your answer.
(2 marks)
-Suggestion: Heat for Longer.
-Justification: You can be sure all of/more of the water has been driven off.
Deduce the Oxidation State of Chlorine in HClO and the Oxidation State of Chlorine in HCl.
(1 mark)
-HClO: +1
-HCl: -1
Chlorine is Reacted with Cold, Aqueous Sodium Hydroxide in the manufacture of Bleach.
Give an Equation for this Reaction between Chlorine and Sodium Hydroxide.
(1 mark)
2NaOH + Cl2 —–> NaCl + NaClO + H2O
Explain how Ions are Detected and Relative Abundance is Measured in a TOF Mass Spectrometer.
(2 marks)
-Detected: When Ion hits the Detector & Gains an Electron.
-Abundance Determined: By size of Current that Flows when it hits the Detector.
There are two Lone Pairs of Electrons on the Oxygen Atom in a Molecule of Oxygen Difluoride (OF2).
Explain how the Lone Pairs of Electrons on the Oxygen Atom influence the Bond Angle in Oxygen Difluoride.
(2 marks)
-Lone Pairs Repel More than Bond Pairs
-Bond Angle will be Lower (103’-106’)
Silicon Tetrafluoride (SiF4) is a Tetrahedral Molecule.
Deduce the type of Intermolecular Forces in SiF4.
Explain how this type of Intermolecular Force arises and why no other type of Intermolecular Force exists in a sample of SiF4.
(3 marks)
-Intermolecular Forces in SiF4: Van der Waals Forces.
Explanation:
-One Molecule Induces Dipole in nearby Molecules.
-Symmetrical Dipoles cancel out.
How many Protons are there in 6.0g of Nitrogen Gas?
(Avogadro Constant = 6.022*10^23 mol^-1) (1)
A) 1.3x10^23
B) 9.0x10^23
C) 1.8x10^24
D) 3.6x10^24
C) 1.8x10^24
Which substance is used to Reduce Titanium(IV) Chloride in the Extraction of Titanium metal? (1)
A) Magnesium
B) Manganese
C) Vanadium
D) Zinc
A) Magnesium
Which statement about Barium Sulfate is correct? (1)
A) It is Soluble in Water at a Temperature of 100°C.
B) It is used in medicine because it does not Dissolve in body fluids.
C) It is a pale yellow solid.
D) It Reacts with Acidified Barium Chloride Solution.
B
Which statement is correct about the Reaction between Concentrated Sulfuric Acid and Solid Sodium Bromide? (1)
A) Bromide Ions are Reduced.
B) Hydrogen Bromide and Sulfur are Formed.
C) Sulfuric Acid acts as an Oxidising Agent.
D) Bromine and Hydrogen Sulfide are Formed.
C
Which Compound is used to treat the symptoms of Indigestion? (1)
A) MgO
B) Mg(OH)2
C) CaO
D) Ca(OH)2
B
Which Element has the Highest First Ionisation Energy? (1)
A) Aluminium
B) Phosphorus
C) Silicon
D) Sulfur
B
Which suggestion would improve the chances of obtaining Concordant Titres? (1)
A) Invert the Volumetric Flask several times after adding the Distilled Water.
B) Wash the Pipette with Distilled Water between each Titration.
C) Add extra drops of Indicator to the sample when nearing the end point in each Titration.
D) Use a more Concentrated Solution of Sodium Hydroxide in the Burette.
A
Which suggestion about rinsing the Conical Flask between each Titration would improve the Accuracy of the Titrations? (1)
A) Rinsing with Acid
B) Rinsing with Alkali
C) Rinsing with Water
D) No Rinsing with any Liquid
C
