Bonsoir les amis ,demain j'ai un examen de chimie en solution et je veux bien que vous m'aider à faire ce exercice s'il vous plait calculer la qantite de nacl et de l'eau nécessaire pour l'obtention de 250g solution de nacl avec le pourcentage massique 10%

Dans 250 g de solution il y a 250×0,1 = 25g de chlorure de sodium.

Masse d'eau: 250g-25g = 225 g

masse volumique de l'eau 1 g cm-3 ; volume d'eau : 225 mL.

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance

the answer is b & c i believe : )