Answer:
The two elements are POLONIUM and RADIUM.
Explanation:
Maria Curie is a French physicist and chemist, though she was of a Polish naturals. She was the first woman to receive a Noble Price which she earned for conducting leading and head way research on radioactivity. She discovered the theory of radioactivity; also the techniques isolating radioactive isotopes. These helped her and her husband discover Polium and Radium.
They are too small to see with the naked eye
Answer:
Kr-81 is most stable because of its high half lige and kr-73 is the most radioactive because of its least half life
Explanation:
Stability is directly proportional to half life of a reaction
Because the coldness in the ice cream and the suns gamma rays are hitting the ice cream and then it will start to melt. and that is why ice cream melts.
Answer:
8.0 mol O₂
Explanation:
Let's consider the complete combustion reaction of C₉H₁₂.
C₉H₁₂ + 12 O₂ → 9 CO₂ + 6 H₂O
The molar ratio of C₉H₁₂ to O₂ is 1:12. The moles of O₂ required to react with 0.67 moles of C₉H₁₂ are:
0.67 mol C₉H₁₂ × (12 mol O₂/1 mol C₉H₁₂) = 8.0 mol O₂
8.0 moles of O₂ are required to completely react with 0.67 moles of C₉H₁₂.
