Answer:
Problem Details
The element europium exists in nature as two isotopes: 151Eu has a mass of 150.9196 amu, and 153Eu has a mass of 152.9209 amu. The average atomic mass of europium is 151.96 amu. Calculate the relative abundance of the two europium isotopes.
answer:
151Eu = 48%, 153Eu = 52%
Answer:
neon is the Noble gas but I have not studied this much
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Answer:
B
Explanation:
We are talking about the periodic table in which elements where put under different rows and columns according to their atomic number (number of protons) in ascendant order.
In rows or periods we can find trends in some properties like atomic radius, electronegativity, etc...). So they are not similar in size. Option A is a false statement.
Also, they were organized in groups or columns according to their similar electronic configuration and chemical properties (like noble gases, halogens, etc...) This means option B is the correct statement.
Answer:
Nuclear Charge
Explanation:
As we move from sodium to chlorine across, there's increase in atomic number (protons). This also means there is increase in the valence electrons (The valence electrons is denoted by the group).
As the number of protons increases, the nuclear energy also increases. Due to this, the electrons are attracted more strongly and pulled closely to the nucleus.