If an endothermic reaction occurs in water, the relationship of the water's final temperature, tf, to its initial temperature, ti, will be

Final temperature of water is lesser.

Explanation:

An endothermic reaction means that reactant absorbs heat from surroundings, meaning that temperature of water decreases for the endothermic reaction.

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons