<Dd> <Dl> <Dd> V m = ∑ i = 1 N x i M i ρ m i x t u r e (\ displaystyle V_ (\ rm (m)) = (\ frac (\ displaystyle \ sum _ (i = 1) ^ (N) x_ (i) M_ (i)) (\ rho _ (\ mathrm (mixture))))). </Dd> </Dl> </Dd> <Dl> <Dd> V m = ∑ i = 1 N x i M i ρ m i x t u r e (\ displaystyle V_ (\ rm (m)) = (\ frac (\ displaystyle \ sum _ (i = 1) ^ (N) x_ (i) M_ (i)) (\ rho _ (\ mathrm (mixture))))). </Dd> </Dl> <Dd> V m = ∑ i = 1 N x i M i ρ m i x t u r e (\ displaystyle V_ (\ rm (m)) = (\ frac (\ displaystyle \ sum _ (i = 1) ^ (N) x_ (i) M_ (i)) (\ rho _ (\ mathrm (mixture))))). </Dd> <P> But this is violated by many liquid - liquid mixtures . For instance mixing pure ethanol into pure water causes a decrease in the volume calculated by this formula . This effect is called "excess volume". </P>

Volume of 1 mol of water at stp