1) Nuclear reactions involve a change in an atom's nucleus, usually producing a different element. Chemical reactions, on the other hand, involve only a rearrangement of electrons and do not involve changes in the nuclei. ... (3) Rates of chemical reactions are influenced by temperature and catalysts.
Cu =63.5
2 times N =28.02
6 times O =96
96=63.5=28.02=127.07
122/127.07=.96 molecules
Answer:
Option D. 4.02 kJ
Explanation:
A simple calorimetry problem
Q = m . C . ΔT
ΔT = Final T° - Initial T°
C = Specific heat capacity
m = mass
Let's replace the data
Q = 125 g . 2.42 J/g∘C . (34.8°C -21.5 °C)
Q= 4023.25 J
We must convert the answer to kJ
4023.25 J . 1kJ /1000 =4.02kJ
Scientists use scientific notation to simplify numbers, basically. When dealing with really big numbers or really small numbers, the usage of scientific notation prevents them from having to write a bunch of zeroes.
Hope that helped you!
