Question

Mention all formulas from the lesson- Some basic concepts of chemistry.

Answer 1

1. Number of molecules in W(g) of substance $=\frac{\mathrm{W}\times {\mathrm{N}}_{\mathrm{A}}}{\mathrm{M}(\mathrm{Molecular}\mathrm{mass})}$
2. ​Molality $\mathrm{m}=\frac{\mathrm{No}.\mathrm{of}\mathrm{moles}\mathrm{of}\mathrm{solute}}{\mathrm{Mass}\mathrm{of}\mathrm{solvent}\left(\mathrm{kg}\right)}$
3. Number of molecules in V litres$=\frac{\mathrm{V}\times {\mathrm{N}}_{\mathrm{A}}}{22.4\mathrm{L}}$ of gas at STP
4. Number of gram atoms $=\frac{\mathrm{W}}{{\mathrm{G}}_{\mathrm{AM}}(\mathrm{gram}\mathrm{atomic}\mathrm{mass})}$
5. Number of gram molecules $=\frac{\mathrm{W}}{{\mathrm{G}}_{\mathrm{MM}}(\mathrm{gram}\mathrm{molecular}\mathrm{mass})}$
6. Dilution formula: ${\mathrm{M}}_1{\mathrm{V}}_1={\mathrm{M}}_2{\mathrm{V}}_2$ for mixing two solutions of the same substance, ${\mathrm{M}}_1{\mathrm{V}}_1+{\mathrm{M}}_2{\mathrm{V}}_2={\mathrm{M}}_3({\mathrm{V}}_1+{\mathrm{V}}_2)$
7. Molarity can be directly calculated from % by mass if density(d) is known; $\mathrm{Molarity}=\frac{\%\times 10\times \mathrm{d}}{{\mathrm{G}}_{\mathrm{MM}}}$
8. Mass of 1 atom of element $=\frac{{\mathrm{G}}_{\mathrm{AM}}(\mathrm{gram}\mathrm{atomic}\mathrm{mass})}{{\mathrm{N}}_{\mathrm{A}}}$
9. Mass of 1 molecule of substance $=\frac{{\mathrm{G}}_{\mathrm{MM}}(\mathrm{gram}\mathrm{molecular}\mathrm{mass})}{{\mathrm{N}}_{\mathrm{A}}}$
10. Temperature in kelvin can be converted to degree Celsius as $\mathrm{T}\left(\mathrm{K}\right)=\mathrm{T}\left({}^{\mathrm{o}}\mathrm{C}\right)+273.15$
11. Relative atomic mass $=\frac{\mathrm{Mass}\mathrm{of}\mathrm{an}\mathrm{atom}\mathrm{of}\mathrm{the}\mathrm{element}}{{\displaystyle \frac{1}{12}}\times \mathrm{Mass}\mathrm{of}\mathrm{carbon}\mathrm{atom}(\mathrm{C}-12)}$
12. Number of molecules in n moles of substance$=\mathrm{n}\times {\mathrm{N}}_{\mathrm{A}}$
13. Mass % of an element in a compound $=\frac{\mathrm{Mass}\mathrm{of}\mathrm{element}}{\mathrm{Molar}\mathrm{mass}\mathrm{of}\mathrm{compound}}\times 100$
14. Mass percent$=\frac{\mathrm{Mass}\mathrm{of}\mathrm{solute}}{\mathrm{Mass}\mathrm{of}\mathrm{solution}}\times 100$
15. $\frac{{\mathrm{X}}_{\mathrm{B}}}{1-{\mathrm{X}}_{\mathrm{B}}}=\frac{\mathrm{Molality}\times {\mathrm{M}}_{\mathrm{A}}}{1000}[\mathrm{where}{\mathrm{M}}_{\mathrm{A}}=\mathrm{Mass}\mathrm{of}\mathrm{solvent}(\mathrm{g}\left)\right]$
    
16. $\mathrm{Molarity}\left(\mathrm{M}\right)=\frac{\mathrm{No}.\mathrm{of}\mathrm{moles}\mathrm{of}\mathrm{solute}}{\mathrm{Volume}\mathrm{of}\mathrm{solution}\left(\mathrm{L}\right)}$
17. $\mathrm{Avogadro}\text{'}\mathrm{s}\mathrm{No}.{\mathrm{N}}_{\mathrm{A}}=6.022\times {10}^{23}$
18. $\mathrm{T}\left({}^{\mathrm{o}}\mathrm{F}\right)=\frac{9}{5}\mathrm{T}\left({}^{\mathrm{o}}\mathrm{C}\right)+32$
19. $\mathrm{Molecular}\mathrm{mass}=2\times \mathrm{Vapour}\mathrm{density}$
20. $\mathrm{Mole}\mathrm{fraction}\mathrm{of}\mathrm{A}=\frac{\mathrm{No}.\mathrm{of}\mathrm{moles}\mathrm{of}\mathrm{A}}{\mathrm{No}.\mathrm{of}\mathrm{moles}\mathrm{of}\mathrm{A}+\mathrm{No}.\mathrm{of}\mathrm{moles}\mathrm{of}\mathrm{solution}}$