Fortification of food with iron is done using $\mathrm{FeSO}_{4} .7 \mathrm{H}_{2} \mathrm{O}$. The mass in grams of the $\mathrm{FeSO}_{4} .7 \mathrm{H}_{2} \mathrm{O}$ required to achieve 12 ppm of iron in 150 kg of wheat is _______ (Nearest integer).} (Given : Molar mass of $\mathrm{Fe}, \mathrm{S}$ and O respectively are 56,32 and $16 \mathrm{~g} \mathrm{~mol}^{-1}$ )
To determine the mass of $\mathrm{FeSO}_{4} \cdot 7 \mathrm{H}_{2} \mathrm{O}$ needed to achieve 12 ppm of iron in 150 kg of wheat, follow these steps:
Define ppm: 1 ppm is 1 mg of solute per 1 kg of solution. Therefore, for 12 ppm of iron in 150 kg of wheat, the mass of iron needed is:
\( \text{Mass of Fe} = 12 \,\text{mg/kg} \times 150 \,\text{kg} = 1800 \,\text{mg} = 1.8 \,\text{g} \)
To find the mass of $\mathrm{FeSO}_{4} \cdot 7 \mathrm{H}_{2} \mathrm{O}$, start by calculating its molar mass:
| Element | Atomic Mass (g/mol) | Atoms | Total (g/mol) |
| Fe | 56 | 1 | 56 |
| S | 32 | 1 | 32 |
| O | 16 | 11 (4+7) | 176 |
| H | 1 | 14 (2x7) | 14 |
| Total | 278 g/mol | ||
Calculate the moles of $\mathrm{Fe}$ in 1.8 g:
\( \text{Moles of Fe} = \frac{1.8 \,\text{g}}{56 \,\text{g/mol}} \approx 0.03214 \,\text{mol} \)
Convert moles of $\mathrm{Fe}$ to moles of $\mathrm{FeSO}_{4} \cdot 7 \mathrm{H}_{2} \mathrm{O}$ since each unit contains one Fe atom:
\( \text{Moles of } \mathrm{FeSO}_{4} \cdot 7 \mathrm{H}_{2} \mathrm{O} = 0.03214 \,\text{mol} \)
Find the mass of $\mathrm{FeSO}_{4} \cdot 7 \mathrm{H}_{2} \mathrm{O}$:
\( \text{Mass} = 0.03214 \,\text{mol} \times 278 \,\text{g/mol} \approx 8.936 \,\text{g} \)
Round to the nearest integer: 9 g
Verify the solution is within the range 9–9. It is correct.
Therefore, the mass of $\mathrm{FeSO}_{4} \cdot 7 \mathrm{H}_{2} \mathrm{O}$ required is 9 g.
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)

Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)
A black body is at a temperature of 2880 K. The energy of radiation emitted by this body with wavelength between 499 nm and 500 nm is U1, between 999 nm and 1000 nm is U2 and between 1499 nm and 1500 nm is U3. The Wien's constant, b = 2.88×106 nm-K. Then,