Using the values when H 2 kept constant rate of reaction y3 compared to 075 is

Using the values when h 2 kept constant rate of

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Using the values when [H 2 ] kept constant, rate of reaction y=3 compared to 0.75 is 4 times, hence conclusion [NO] = 1.0 mol dm -3 is double that of value of z, hence z = 0.5 mol dm -3 15 Answer: D A is incorrect as ionic radius of M 2+ would increase down Group 2, hence charge density would decrease B is incorrect as atomic radius of elements would increase down Group 2, hence electronegativity would decrease C is incorrect as the number valence electrons in Group 2 is always 2 D is correct as the cationic size of M 2+ would increase down Group 2, hence its charge density and polarizing power would decrease. Hence less able to distort the electron cloud of large nitrate anion and weakening the covalent bonds between N and O atoms, hence thermal decomposition would take place at a higher temperature, leading to thermal stability of the nitrate 16 Answer: D A is not true as S also gives 2 acidic oxides SO2 and SO3 B is not as Ne has the highest 1 st IE in period 3 C is not true there are chlorides of Mg, Si and S that gives acidic solutions D is true as P forms P 4 molecule with 4 atoms
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H2 Chemistry 9647 2015 17 Answer: A Cu + is colourless due to d 10 electronic configuration. Copper (II) hydroxide is a blue precipitate. 18 Answer: C Atomic radii decreases across the Period 3 due to increasing nuclear charge while shielding effect remains effectively constant (because in the same period). Effective nuclear charge increases and thus atomic radii of P < Si < Al < Mg Across Period 3, melting point increases from Mg to Al (due to increasing metallic bond), with Si having the highest melting point (due to strong covalent bonds between Si atoms), then drop significantly for P 4 (which exists as simple molecular structure with weak id-id between
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