Answer:
The repeating nature of physical and chemical properties with atomic number
Explanation:
Periodic table is designed in a way in which elements are divided in groups and periods. Periods are rows and groups are columns. The elements in groups share similar properties due to the same number of valence electrons they have. Going along each period, we'll always get back to the same group at some point. This is why we have periodic trends, the trends repeat gradually when we finally reach the same group we're analyzing.
Physical and chemical properties vary periodically. For example:
- atomic radius decreases from left to right along the period;
- ionization energy increases from left to right along the period;
- electronegativity increases from left to right along the period;
- metallic properties decrease from left to right along the period.
The atomic mass of rubidium listed in the periodic table to determine the mass of Rb−87 is 86.13 amu.
<h3>What is atomic mass?</h3>
The atomic mass is the weight of the roton neutron and electron present inside the nucleus and shells of an atom and the elements are arranged on the basis of this only.
The mass of Rb−85 is 84.9118 amu for 1 amu it will be
amu = 84.9118 / 85 = 0.99
so, the amu for Rb−87 will be,
AMU = 87 × 0.99 = 86.13 amu.
Therefore, the mass of Rb−87 is 86.13 amu for atomic mass of rubidium listed in the periodic table.
Learn more about atomic mass, here:
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The answer is false. It is because the electron structure of
the atom is not determined by using the direct observation of using an x-ray
but rather the usage of theoretical modeling and the emission spectra will be useful
in observing.
Answer:
A mutation in Jackie's genes culminated in developing a new enzyme, resulting in the long-distance running phenotype. Jackie appears to have either the A1Am or A2Am gene variants. Jackie used to play for long periods without tiring, suggesting that her gene variants could generate a protein that results in a stamina feature. Jackie's father bears the A1A2 gene. Since Jackie's mother is a good sprinter, I suspect she bears A1A1 gene variants. Sprinters have much ACTN3 protein in their cells, so that she may have two copies of the A1 gene variant. This means Jackie has at least one clone of the A1 gene allele. People with one or two versions of the A1 gene variant, on the other hand, are rarely successful long-distance runners. Out of 100 total distance runners, only 28 (25 and 3) have an A1 gene copy. Since the gene variants she may have inherited from her parents cannot justify her stamina, she may have a mutant gene version that contains a long-distance running protein. However, I do not believe she has AmAm gene versions because mutations are uncommon. Jackie is an elite long-distance runner due to a gene that no one else in her family has.