I'm not sure, but maybe burning point...
Answer:
The correct answer would be - c. A solid was added to water and the mixture was stirred until the solid was no longer visible
Explanation:
Photostabalizing is the process where a solid change its color in the presence of ultraviolet light, it is a chemical change, so the first option would not be the correct answer.
when two liquid or aqueous solutions are mixed together and form a solid substance, this reaction is known as precipitation and it is a chemical reaction too.
When a solid is placed in a liquid and after stirring it makes the solid vanish is a physical change known as dissolving character.
Thus, the correct answer is option C.
I believe the correct term to fill in the blank would be ionic. A molecule of common table salt, or nacl, is the result of ionic bond forming between a sodium (na) atom and a chlorine (cl) atom. Ionic bonding is a result of complete transfer of electrons between atoms. It usually happens between a metal and a nonmetal.
Scientist rely on their estimates when they cannot obtain on exact numbers
The formula to convert from Celsius to Fahrenheit is F = 9/5C + 32 or F = (C*1,8)+32
F = 9/5*39 + 32 = 70,2 + 32 = 102,2° F