I don't know much about this, but probably the reason why your teacher circled 300k is because of what's in the photo below. If you couldn't tell from the photo, its because 300k isn't negative. Anyway this is my guess, based on my limited knowledge.
Balance your chemical reaction first. Start by balancing carbon so you have 2 carbons on both sides.
C2H6 + O2 —> 2CO2 + H2O
Now balance your hydrogen so you have 6 hydrogens on both sides.
C2H6 + O2 —> 2CO2 + 3H2O
Now balance your oxygens. You have 7 oxygens on the right and 2 on the left, so multiply O2 by 3.5.
C2H6 + 3.5O2 —> 2CO2 + 3H2O
However, you can’t have a decimal in a coefficient. So, multiply everything by two.
2C2H6 + 7O2 —> 4CO2 + 6H2O
Now use your mole ratio of 6 mol H2O for every 2 mol of C2H6 to solve.
1.4 mol C2H6 • 6 mol H2O / 2 mol C2H6 = 4.2 mol H2O
D) 4.2 moles
Both Chemical and Nucleus Reactions form new substances.
Mark me as brainliest if I helped:)
This equation is impossible. NaSO4 is non-existent. Did you mean Na2SO4?
A doesn't change the model, that's what google's for, B can be easily used with the current model, and D is ridiculous.
The model of, for example, the atom, has changed over the years with multiple experiment sand multiple models. There was plum pudding, for example, with protons and electrons scattered throughout, until Rutherford's experiments (a new discovery) changed that because he found a dense nucleus.
The answer pops out at you
