Réponse :
Bonjour,
M( C₆H₂₂O₆ ) = 6 × M( C ) + 22 × M( H ) + 6 × M( O )
= 6 × 12 + 22 × 1 + 6 × 16
= 190 g·mol⁻¹
[tex]C_m = \dfrac{m}{v}\\\\= \dfrac{250}{2}\\\\= \mathbf{125 \ g \cdot L^{-1}}[/tex]
[tex]n = \dfrac{m}{M}\\\\= \dfrac{250}{190}\\\\= 1,32 \ mol[/tex]
[tex]c = \dfrac{n}{v}\\\\= \dfrac{1,3}{2}\\\\= \mathbf{0,66 \ mol \cdot L^{-1}}[/tex]