Light does not travel at a constant speed in a vacuum, compared to in air, because the light is being absorbed by atoms and molecules in the air. But light does travel at a constant speed in a vacuum.
So I agree with A
All that talk about moving forward is irrelevant (I think)
From the equation of the reaction; for every 1 mole of copper, the reaction uses 2 moles of silver nitrate.
<h3>What is a reaction?</h3>
A chemical reaction involves the transformation of one chemical specie into another. The reaction is not shown here hence the question is incomplete.
However, the reaction should be of the sort; Cu + 2AgNO3 ---> Cu(NO3)2 + Cu. Thus, for every 1 mole of copper, the reaction uses 2 moles of silver nitrate.
Learn more about chemical reaction: brainly.com/question/6876669
Burning charcoal is a chemical reaction called combustion
<span>NO2 weighs 46.005 grams per mol. There are 6.02x10^23 molecules in a mol. In the given sample of 189.5 grams, there are 4.12 mols. This means that there are 2.48x10^24 molecules of NO2 in the given sample.</span>
