Answer:
0.171 grams of oxygen combined with the metal.
Explanation:

Mass of magnesium oxide produced = 0.421 g
Mass of magnesium metal used = 0.250 g
Suppose reaction completely converts the magnesium into magnesium oxide.
Mass of oxygen combined with magnesium = m
0.421 g = 0.250 g + m
m = 0.421 g - 0.250 g = 0.171 g
0.171 grams of oxygen combined with the metal.
3–ethyl–2,4–dimethylhexane
CH₃-CH(CH₃)-CH(C₂H₅)-CH(CH₃)-CH₂-CH₃
Answer
Two different elements have similar chemical properties when they have the same number of valence electrons in their outermost energy level. ... Elements in the same column of the Periodic Table have the same number of valence electrons – that's why they have similar chemical properties.
Answer: Most ocean pollution begins on land
When large tracts of land are plowed, the exposed soil can erode during rainstorms. Much of this runoff flows to the sea, carrying with it agricultural fertilizers and pesticides. Eighty percent of pollution to the marine environment comes from the land.
Explanation:
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