"if it is tested in a controlled setting with repeated results" is the statement among the choices given in the question that best describes that can possibly make this scientific claim valid. The correct option among all the options that are given in the question is the first option or option "A". I hope the answer has helped you.<span>
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Answer:
pineal body is a vastigious structure which signifies same origin of chimpanzee and modern man
Explanation:
The elements in the periodice table are not listed in alphabetical order, because the arragement in rows (periods) and columns (groups or familes), in increasing order of atomic number (number of protons of the atoms) permits to explain similarities among the elements, trend in some properties, and even predict properties of unknown elements.
For example, the elements of the first group (family), called alkaline metals, all have 1 valence electron, have similar physical properties (ductibility, malleability, luster, thermal and electricity conductivity), react in similar way with water, show a trend in the atomic radii and in the ionization energy.
You can tell similar stories for other groups like, alkalyne earth metals, halogens and noble gases.
You can also tell trends in electroneativities, and atomic radii, for a row of elements, as per the order they are in the row.
So, the current array resulted very helpul for chemists to explain and predict the behavior and properties of the elements.
As you move from left to right across a period,the number of valence electrons<span>-increases. </span>
For each ionic compound formula, identify the main group to group 17 (VIIA).
Group17 (VIIA) is the primary group to which X belongs in each ionic combination with the formula CaX2. X is undoubtedly an electron acceptor. It is capable of taking an electron. We determine that X must be in the oxidation state -1 by looking at the chemical formula. The neutral ionic compound's total number of oxidation states is zero. Since calcium has an oxidation state of +2, we must identify the element that contains an anion with an oxidation state of -1. The halogens have a strong propensity to pick up an electron and create an anion. X belongs to group17 (VIIA) as a result.
To know more about ionic compound formula refer the link:
brainly.com/question/9597623
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