A. When two chemicals mix their temperature rise: <span>Exothermic
b. </span>A solid burns brightly and releases heat, light and sound: <span>Exothermic
c. </span>When two chemicals are mixed their temperature drops: <span>Endothermic
d. </span>Two chemicals will only react if you heat them continually: <span>Endothermic
e. </span>Plants take in light energy for photosynthesis: <span>Endothermic
I hope this helps :)</span>
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.
It is a reaction between an element and a compound that results in a different element and compound
Answer: increases by
As a chlorine atom becomes a negative ion, the atom "increases by" an electron
Explanation:
Chlorine atom has an atomic number of 17, and an electronic configuration of 1s2, 2s2 2p6, 3s2 3p5 showing 7 valence electrons in its outermost shell.
Hence, it receives a single electron to achieve a stable octet structure with electronic configuration of
1s2, 2s2 2p6, 3s2 3p6. Therefore, Cl- is a univalent negative ion with 8 valence electrons in its outermost shell. The increase is shown below
Cl + e- --> Cl-
Thus, as a chlorine atom becomes a negative ion, the atom "increases by" an electron
Im pretty sure its melting ice