Density

... and wanna make 1L of a 0.4M solution you just add 400 mL of your 1M solution and 600 mL of water. You don't even need to know molecular weight, density or anything else. You can just derive it out of C1*V1=C2*V2 (1M*V1=0.4M*1L and solve for V1)

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... of acetic acid and sodium acetate to achieve the required pH. How would you make up 1 L of the acetic acid stock solution (0.4 M CH3COOH)? The density of the liquid is 1.05 g/mL and the molecular weight is 60.

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... site). It is more than just shape that is of concern here, it is the electrostatic topology of the active site. Areas of higher or lower electron density relative to the nuclear charge in that region lead to binding or repulsion of substrate molecule(s) and make groups more or less reactive. Changing ...

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or measure the optical density,provided you keep a control without the substance

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In an experiment it is found that the optical density of a solution of compound X was 0.7 when measured at 400nm. in a 1cm glass cuvette. The solution had been prepared by dissolving 35mg of X in 50 ml of water. What is the molar extinction coefficient ...

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