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What is the concentration of a solution containing 2g of NaOH in 100cm3 of solutio...



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  • Mass = 2g, Molar mass of [NaOH]= [23+16+1]=40gmol-¹, volume= 100\( cm^3 \); Recall 1000\( cm^3 \)=1\( dm^3 \)
    Volume=\( \frac{100 × 1}{1000}= 0.1 \)\( dm^3 \)
    No of moles= \( \frac{mass}{molar mass} \)
    No of moles= \( \frac{2g}{40gmol^-1} \
    No of moles= 0.05moles
    Conc. in \( moldm^-3 \)= \( \frac{0.05 moles}{0.1dm^-3} \)
    Conc in \( moldm^-3 \)=\( 0.5moldm^-3 \
    Option [B] is the appropriate answer.

  • NaOH=40(23+16+1)..
    n=mass/molar mass I.e 2/40=0.05mole
    0.05=100cm³
    X=1000cm³
    =0.5moldm³

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