How many joules of heat are given off when 50 g of liquid water at 30℃ freezes to ice?

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

catya your not at all which answer i've seen you do this on another question!

metric time was an attempt to create a standard unit of time based off of 10, but it never took off an is not included in the metric system (si)