Answer:
Astatine is a halogen with several isotopes that all have short half-lives.
Which of the following combinations of mass number and neutrons are possible as isotopes of astatine? Choose one or more:
i) A = 211, n = 127
ii) A = 210, n = 125
iii) A = 220, n = 134
iv) A = 207, n = 122
v) A = 209, n = 124
Explanation:
The mass number is the sum of the number of protons and the number of neutrons in an atom.
Atomic number of At(astatine ) =85
That means it has --- 85protons.
Its mass number A=210
Hence, the number of neutrons in At are:
Second option:
ii) A=210 , n=125 is the answer.
Answer:Noble gases:
are highly reactive.
react only with other gases.
do not appear in the periodic table.
are not very reactive with other elements.
Explanation:Noble gases:
are highly reactive.
react only with other gases.
do not appear in the periodic table.
are not very reactive with other elements.
Regretfully, I do not know what is asked of the problem because it is not stated above. However, it is easier to answer any question pertaining to the temperature, volume, and pressure of gases by assuming that they behave ideally. With this, we'll be able to use the ideal gas law which is mathematically expressed as,
PV = nRT
where P and V are pressure and volume, respectively. n is the amount of material in mol, R is gas constant, and T is temperature.
Answer:
A dominant allele produces a dominant phenotype in individuals who have one copy of the allele, which can come from just one parent. For a recessive allele to produce a recessive phenotype, the individual must have two copies, one from each parent.
Explanation:
A dominant allele becomes a trait even if just one copy of it is present. A recessive allele does not become a trait unless both copies of the gene, one from mom and one from dad, are present. If one dominant allele and one recessive allele are present, the dominant allele trait will be expressed.
Only individuals with an aa genotype will express a recessive trait; therefore, offspring must receive one recessive allele from each parent to exhibit a recessive trait.
I’d say market and distribution would be the next step
