⁷⁰₂₉Cu
Explanation:
Copper-70 isotope in nuclide form.
A nuclide is designated as: ₙᵇX
Where X is the symbol of the atom
b is the mass number of the atom
n is the atomic number
Mass number is the number of protons and neutrons in an atom. These particles makes up the bulk of the mass of an atom.
Atomic number is the number of protons in an atom. For neutral atom, it is the same as the number of electrons.
To write Copper-70 in nuclide format:
Symbol of Copper is Cu
Mass number is 70
Atomic number from periodic table is 29
⁷⁰₂₉Cu
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Atomic number brainly.com/question/5425825
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The mass of piece of sterling silver jewelry is 33.24 g. It contains 92.5% silver Ag by mass. Since, sterling silver is an alloy of Ag-Cu thus, percentage of Cu will be:
% Cu=100-92.5=7.5%
Thus, mass of copper will be:

Molar mass of Cu is 63.546 g/mol, thus, number of moles of Cu can be calculated as follows:

Here, m is mass and M is molar mass.
Putting the values,

Now, in 1 mole of Cu there are
thus, in 0.03923 mol, number of Cu atoms will be:

Thus, number of atoms of Cu will be
.
Answer:
first ionization energy is the amount of energy required to remove an electron from isolated gaseous atom
so when atomic no increase across aperiod the ionization energy become lower
it's my opinion am not sure ok