What defines endothermic reactions and exothermic reactions? Select all that apply.
A) Endothermic reactions are chemical reactions that absorb energy from the surrounding environment.
B) Exothermic reactions are chemical reactions that release energy into the surrounding environment.
C) Exothermic reactions are chemical reactions that absorb energy from the surrounding environment.
D) Endothermic reactions are chemical reactions that release energy into the surrounding environment.

2points what is the job of a scientist? a. to answer ethical questions. b. to write laws based on his or her knowledge. c. to ask and answer scientific questions. d. to ignore facts that do not support his or her theory.

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.

Which statement are accurate about snow flakes