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\( 200 \, \text{cc} \) of \( x \times 10^{-3} \, \text{M} \) potassium dichromate is required to oxidise \( 750 \, \text{cc} \) of \( 0.6 \, \text{M} \) Mohr’s salt solution in acidic medium. Here \( x = \) __________.

\( 500 \, \mathrm{mL} \) of \( 0.2 \, \mathrm{M} \) \( \mathrm{MnO_4^-} \) solution in basic medium when mixed with \( 500 \, \mathrm{mL} \) of \( 1.5 \, \mathrm{M} \) \( \mathrm{KI} \) solution, oxidises iodide ions to liberate molecular iodine. This liberated iodine is then titrated with a standard \( x \, \mathrm{M} \) thiosulphate solution in presence of starch till the end point. If \( 300 \, \mathrm{mL} \) of thiosulphate was consumed, then the value of \( x \) is ________.

Consider the following reduction processes:
\( \mathrm{Al^{3+}} + 3e^- \rightarrow \mathrm{Al(s)}, \ E^\circ = -1.66 \, \text{V} \)
\( \mathrm{Fe^{3+}} + e^- \rightarrow \mathrm{Fe^{2+}}, \ E^\circ = +0.77 \, \text{V} \)
\( \mathrm{Co^{3+}} + e^- \rightarrow \mathrm{Co^{2+}}, \ E^\circ = +1.81 \, \text{V} \)
\( \mathrm{Cr^{3+}} + 3e^- \rightarrow \mathrm{Cr(s)}, \ E^\circ = -0.74 \, \text{V} \)
The tendency to act as reducing agent decreases in the order:

$500\text{ mL}$ of $1.2\text{ M }\text{KI}$ solution is mixed with $500\text{ mL}$ of $0.2\text{ M }\text{KMnO}_4$ solution in basic medium. The liberated iodine was titrated with standard $0.1\text{M }\text{Na}_2\text{S}_2\text{O}_3$ solution in the presence of starch indicator till the blue color disappeared. The volume (in L) of $\text{Na}_2\text{S}_2\text{O}_3$ consumed is ______________. (Nearest integer)

Complete combustion of \( X \) g of an organic compound gave \( 0.25 \) g of \( \mathrm{CO_2} \) and \( 0.12 \) g of \( \mathrm{H_2O} \). If the \( \% \) of carbon is \( 25\% \) and of hydrogen is \( 4.89\% \), then \( X = \) ______ \( \times 10^{-3} \) g. (Nearest integer)

(Molar mass of \( \mathrm{C} \), \( \mathrm{H} \) and \( \mathrm{O} \) are \( 12 \), \( 1 \) and \( 16 \) g \( \mathrm{mol}^{-1} \) respectively.)

In order to oxidise a mixture of \( 1 \) mole each of \( \mathrm{FeC_2O_4} \), \( \mathrm{Fe_2(C_2O_4)_3} \), \( \mathrm{FeSO_4} \) and \( \mathrm{Fe_2(SO_4)_3} \) in acidic medium, the number of moles of \( \mathrm{KMnO_4} \) required is:

Given below are two statements:
Statement I: The correct order of electronegativity of fluorine, oxygen and nitrogen is \( \mathrm{F} > \mathrm{O} > \mathrm{N} \).
Statement II: The oxidation state of oxygen in \( \mathrm{OF_2} \) is \( +2 \) and in \( \mathrm{Na_2O} \) is \( -2 \).
In the light of the above statements, choose the correct answer from the options given below