AS Chemistry AQA paper 1 2019 20th May UNOFFICIAL MARKSCHEME

Hey I'm doing my AS Chemidtry mock exam and teacher is giving us paper sent by AQA will it be this paper?

Did anyone get 92.9 for Mr question?

Can you tell me what came questions came up in AS chem paper

8 questions for Section A, ~14 for Section B? Forgot the order of questions


Q. (a) Na+ and F- have the same electronic configuration, why is Na+ smaller than F-
– Na+ has a greater nuclear charge and therefore the attraction between its nucleus and the electrons is much greater than in F-.

(b) Structure and bonding in NaF (i think)
– Ionic bonding - strong electrostatic forces of attraction between the oppositely charged ions as they are arranged in a regular lattice.

Q. Explain the process of electronspray ionisation.
– Sample is inserted in a fine needle in which it gets vapourised and a high voltage is passed through to produce ions.
Q. Which ion reaches the detector first
– Whatever was the first compound they mentioned.

Q. HF can bond with H+ to form H2F, explain how.
– Dative Covalent bond, two electrons from F are shared with the H+ ion.
Q. Draw and name the shapes of SF6- and H2F+
– SF6- was octahedral and H2F+ was V-shape/bent

Q. Find the bond enthalpy of C-F
484 kJ/mol

Q. Electronic configuration of Cr
Q. Question on Germanium, finding the mass of one mole of Germanium and its atomic mass
– Something x 10^-22, 69

Q. Moles question
(a) Find the moles of the equilibrium mixture
NO2 (i think) = 1.125
Cl2 = 0.825
(b) Kc expression
(c) They changed the moles of the other stuff and gave Kc, find the moles of NO2 (i think)
– 0.073 or something like that

Q. Oxidation state of Cr in Cr2O3-
– +6
Q. Half equation for I ions to I2
Q. Half equation for Cr2O3- in acidic conditions to Cr+3.
Q. Overall equation.

Q. (a) Find the Mr of the acid in a titration experiment.
– Got 98 or 99, somewhere around that.
(b) Percentage uncertainty for the pipette.
– (0.06/25) *100 = 0.24%
(c) Something about an air bubble in the burette.
– The level of the burette would fall even when none of the solution has been delivered to the flask.
(d) Why washing down the flask with distilled water had no effect.
– It was to ensure that all the mixture is in the flask.

Q. Calculate the % mass of MgO (I think) in a mixture.
– I think I got 70 something %

Q. 6 marker on the trend of first ionisation energies for Period 2 elements.
– Overall increase due to reducing atomic radii but decreases for Boron (because it fills a higher energy level) and Oxygen (because it has 2 electrons in one of its 3p orbitals and these two repel).

Q. Test for Ions
(a) NaCl (?) and BaCl2
– Add sulfuric acid, white precipitate for BaCl2.
(b) NaCl (?) and NaCO3.
– Add HCl, effervescence with NaCO3.


Forgot the rest whoops.

Is this aqa?

Is this for the 2019 AS chemistry paper AQA?

8 questions for Section A, ~14 for Section B? Forgot the order of questions


Q. (a) Na+ and F- have the same electronic configuration, why is Na+ smaller than F-
– Na+ has a greater nuclear charge and therefore the attraction between its nucleus and the electrons is much greater than in F-.

(b) Structure and bonding in NaF (i think)
– Ionic bonding - strong electrostatic forces of attraction between the oppositely charged ions as they are arranged in a regular lattice.

Q. Explain the process of electronspray ionisation.
– Sample is inserted in a fine needle in which it gets vapourised and a high voltage is passed through to produce ions.
Q. Which ion reaches the detector first
– Whatever was the first compound they mentioned.

Q. HF can bond with H+ to form H2F, explain how.
– Dative Covalent bond, two electrons from F are shared with the H+ ion.
Q. Draw and name the shapes of SF6- and H2F+
– SF6- was octahedral and H2F+ was V-shape/bent

Q. Find the bond enthalpy of C-F
484 kJ/mol

Q. Electronic configuration of Cr
Q. Question on Germanium, finding the mass of one mole of Germanium and its atomic mass
– Something x 10^-22, 69

Q. Moles question
(a) Find the moles of the equilibrium mixture
NO2 (i think) = 1.125
Cl2 = 0.825
(b) Kc expression
(c) They changed the moles of the other stuff and gave Kc, find the moles of NO2 (i think)
– 0.073 or something like that

Q. Oxidation state of Cr in Cr2O3-
– +6
Q. Half equation for I ions to I2
Q. Half equation for Cr2O3- in acidic conditions to Cr+3.
Q. Overall equation.

Q. (a) Find the Mr of the acid in a titration experiment.
– Got 98 or 99, somewhere around that.
(b) Percentage uncertainty for the pipette.
– (0.06/25) *100 = 0.24%
(c) Something about an air bubble in the burette.
– The level of the burette would fall even when none of the solution has been delivered to the flask.
(d) Why washing down the flask with distilled water had no effect.
– It was to ensure that all the mixture is in the flask.

Q. Calculate the % mass of MgO (I think) in a mixture.
– I think I got 70 something %

Q. 6 marker on the trend of first ionisation energies for Period 2 elements.
– Overall increase due to reducing atomic radii but decreases for Boron (because it fills a higher energy level) and Oxygen (because it has 2 electrons in one of its 3p orbitals and these two repel).

Q. Test for Ions
(a) NaCl (?) and BaCl2
– Add sulfuric acid, white precipitate for BaCl2.
(b) NaCl (?) and NaCO3.
– Add HCl, effervescence with NaCO3.


Forgot the rest whoops.

is tthis for OCR AS paper 2019 ?

is tthis for OCR AS paper 2019 ?

Yes

Anyone have paper 2 markscheme? I can’t find a thread on it anywhere

8 questions for Section A, ~14 for Section B? Forgot the order of questions


Q. (a) Na+ and F- have the same electronic configuration, why is Na+ smaller than F-
– Na+ has a greater nuclear charge and therefore the attraction between its nucleus and the electrons is much greater than in F-.

(b) Structure and bonding in NaF (i think)
– Ionic bonding - strong electrostatic forces of attraction between the oppositely charged ions as they are arranged in a regular lattice.

Q. Explain the process of electronspray ionisation.
– Sample is inserted in a fine needle in which it gets vapourised and a high voltage is passed through to produce ions.
Q. Which ion reaches the detector first
– Whatever was the first compound they mentioned.

Q. HF can bond with H+ to form H2F, explain how.
– Dative Covalent bond, two electrons from F are shared with the H+ ion.
Q. Draw and name the shapes of SF6- and H2F+
– SF6- was octahedral and H2F+ was V-shape/bent

Q. Find the bond enthalpy of C-F
484 kJ/mol

Q. Electronic configuration of Cr
Q. Question on Germanium, finding the mass of one mole of Germanium and its atomic mass
– Something x 10^-22, 69

Q. Moles question
(a) Find the moles of the equilibrium mixture
NO2 (i think) = 1.125
Cl2 = 0.825
(b) Kc expression
(c) They changed the moles of the other stuff and gave Kc, find the moles of NO2 (i think)
– 0.073 or something like that

Q. Oxidation state of Cr in Cr2O3-
– +6
Q. Half equation for I ions to I2
Q. Half equation for Cr2O3- in acidic conditions to Cr+3.
Q. Overall equation.

Q. (a) Find the Mr of the acid in a titration experiment.
– Got 98 or 99, somewhere around that.
(b) Percentage uncertainty for the pipette.
– (0.06/25) *100 = 0.24%
(c) Something about an air bubble in the burette.
– The level of the burette would fall even when none of the solution has been delivered to the flask.
(d) Why washing down the flask with distilled water had no effect.
– It was to ensure that all the mixture is in the flask.

Q. Calculate the % mass of MgO (I think) in a mixture.
– I think I got 70 something %

Q. 6 marker on the trend of first ionisation energies for Period 2 elements.
– Overall increase due to reducing atomic radii but decreases for Boron (because it fills a higher energy level) and Oxygen (because it has 2 electrons in one of its 3p orbitals and these two repel).

Q. Test for Ions
(a) NaCl (?) and BaCl2
– Add sulfuric acid, white precipitate for BaCl2.
(b) NaCl (?) and NaCO3.
– Add HCl, effervescence with NaCO3.


Forgot the rest whoops.

Is this Aqa or OCR?