Complete the following statement by substituting X and Y with correct options: "Corrosion and rancidity are the results of 'X' reaction of iron articles and oils/fats respectively. Galvanisation is done to prevent corrosion of iron articles and 'Y" are used to prevent rancidity of oils or fats". 

The reaction:

 $$\begin{gathered} {\mathrm{Fe}}_2{\mathrm{O}}_3\left(\mathrm{s}\right) + 2\mathrm{Al}\left(\mathrm{s}\right) \to {\mathrm{Al}}_2{\mathrm{O}}_3\left(\mathrm{s}\right) + 2\mathrm{Fe}\left(\mathrm{s}\right) \\ \mathrm{Ferric} \mathrm{oxide} \mathrm{Aluminium} \mathrm{Aluminium} \mathrm{oxide} \mathrm{Iron} \end{gathered}$$

is an example of a 

In the reaction, ${\mathrm{Be}}_2\mathrm{C}+{\mathrm{xH}}_2\mathrm{O}\to \mathrm{yBe}{\left(\mathrm{OH}\right)}_2+{\mathrm{CH}}_4$

The value of x and y are 

Which of the following statements is not true?

Which of the following is not a chemical change? 

In the equation:

${\mathrm{PCl}}_5+{\mathrm{xH}}_2\mathrm{O}\to {\mathrm{H}}_3{\mathrm{PO}}_4+\mathrm{yHCl}$, the value of x and y are

The reaction: $4{\mathrm{NH}}_3\left(\mathrm{g}\right)+5{\mathrm{O}}_2\left(\mathrm{g}\right)\to 4\mathrm{NO}\left(\mathrm{g}\right)+6{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)$  is an example of 

(i) displacement reaction 

(ii) combination reaction 

(iii) redox reaction

(iv) neutralisation reaction 

Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of reaction involved? 

(i) Displacement reaction 

(ii) Combination reaction 

(iii) Precipitation reaction 

(iv) Double displacement reaction