8. a log is burning in a fireplace. if the amount of oxygen reaching the log is decreased, which of the
following statements is true?
the reaction rate increases.
the reaction rate decreases.
the reaction rate remains the same.
the reaction rate only depends on the temperature.

Answer is: The reaction rate decreases.

Balanced chemical reaction of burning log:

C(s) + O₂(g) → CO₂(g).

The reaction rate is the speed at which reactants are converted into products.

Reaction rate depends on concentration (amount) of oxygen.

If amount of oxygen decreases, reaction rate also decreases and vice versa.

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