Answer:
No, glass melting is not a chemical reaction. Reactions may bring about change in substances and may be characterized as chemical or physical change.
Yes. Percent yield shows how efficient one's method is. If his isolated caffeine proved to be at only 1.5%, compared to least 50% as in many of the previous experiments, the student should be very concerned as it shows that something caused the yield to sharply drop.
Answer:
Of course it's C
Red planet
Explanation:
It is because the soil on Mars is rich of Fe (Iron).
That makes the soil look red.
Even on our planet we have such this places like hormuz island in Iran.
30 m/hrs (add me on discord if u have it Sipstic++#1460 )