The answer is B because isotopes have the same number of protons and neutrons.
Carbon dioxide it should be water oxygen
If an element contains 8 electrons, then there would be 6 electrons that will be placed in the 2nd valence shell. Each shell in an atom can only take up a fixed number of electrons. For the first shell, only two electrons can be found. For the second shell, it can hold up to 8 electrons. However, for this case only six electrons can be found since the others are found in the first shell.
C a solution because salt is a solute
Option E, 2, 7, 4, 6. The type of reaction is combustion reaction, as oxygen is being reacted with C2H6 to form new compounds.
Let me know if you need any further explanation :))
-T.B.