Nell'acqua di un acquario da 60 L sono disciolti 480 mg di ossigeno . Qual è la concentrazione dell'ossigeno disciolto?

The given question is :

480 mg of oxygen is dissolved in the water of a 60 L aquarium. What is the concentration of dissolved oxygen?

Given:

Mass of oxygen = 48 mg

48 mg of oxygen is dissolved in the water of a 60 L aquarium

To find,

The concentration of dissolved oxygen.

Solution,

concentration of dissolved oxygen = (mass of water/mass of solution)×100

48 mg = 0.000048 L

So, this is the required solution.

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

thats how its supposed to be