Sendok yang biasa kita gunakan terbuat dari stainless atau campuran baja dengan beberapa logam, namun sendok tidak mudah berkarat padahal yang kita ketahui bahwa logam jika kontak langsung dengan air dan oksigen akan mudah berkarat. Alasan yang benar untuk pernyataan tersebut adalah

screening

explanation:

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

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year