Which of the following was an important discovery that marie curie made while studying? large atoms gain mass through radioactivity atoms can change into different atoms with new properties
all radioactive elements give off the same amount of energy
the number of protons and neutrons in an atom never changes
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The is a particle with one unit of positive charge a. proton b. positron c. electron d. nucleus awnser quick it is a important science test!

How much energy is made when a pice of wood burns. how do you know

Answer asap need to be answered 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.