If the buret is dirty, it will react with the NaOH in the buret and will cause your concentration to be off.
Answer:
Chemical Change
Explanation:
Physical change normally mean that the change can revert back to its orginal state, which in this case that is not possible therfore it is a chemical change.
Answer:
you need to send us the figure
Explanation:
First, it is best to know the chemical formula of pyridine which is C5H5N. To determine the number of carbon atoms present in pyridine, multiply 7.05 mol C5H5N with 5 mol C/ 1 mol C5H5N which then results to 35.35 mol of carbon. Then, multiply the answer to Avogadro's number which is 6.022x10^23 atoms. It is then calculated that the number of carbon atoms in 7.05 moles of pyridine is 2.12x10^25 atoms.
The answer would be a planet<span>. Planets revolve around stars, which means there will come a point where the planet is between the star and our field of vision towards the star. This point will be where the star's radiation will have the lowest intensity. As the planet moves, the intensity will change. The effect is comparable to a lunar or solar eclipse.</span>
