Regarding phases 2 or 3 of the experiment, if more or fewer drops of reagent d (sodium hydroxide) were needed to get the same blue color as in phase 1, what does this tell us about the quality of the water when yeast was consuming nutrients in the water? did something similar to eutrophication occur? **phase 2 used quite a lot more drops than phase 3**

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6

може ли да зареждате повече информация, моля

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8