Answer:
The arrangement of the periodic table leads us to visualize certain trends among the atoms.
Elements are arranged from left to right and top to bottom in order of increasing atomic number.
The vertical columns (groups) of the periodic table are arranged so that all its elements have the same number of valence electrons (outer ring). All elements within a certain group share similar properties.
The rows are called periods. All elements in a row have the same number of electron shells.
Answer:
Scientific theory differs from a guess or opinion because a scientific theory is a system of ideas that explains many related observation and is supported by a large body of evidence acquired through scientific investigation while guesses and opinions may not reliably predict an outcome, have evidence to back up the theory
Explanation:
Let's eliminate these one by one.
The first pair would not be the same, as X would most likely be in group IA, and Y would be in group VIIA, because of their tendency to gain and lose electrons.
The second pair would also violate the same rule, but X would most likely be in group IIA, and Y would most likely be in group VIA.
The third pair would not be the same, as X is most likely in group VIIA, and since Y has eight valence electrons, it is most likely a noble gas.
The final pair has X with atomic number 15, making it phosphorous. Phosphorous wants to gain 3 electrons to have a full octet of 8 outer "valence" electrons, and Y would also like to gain 3 electrons. This means it is possible that the final pair would be in the same group.
2H2O2 decomposes into the products 2H2O + O2(g)
<span>FeNCS+ product...............thats how you do it i believe </span>
