The daughter isotope (a decay product)of O-15 = N-15(Nitrogen 15)
<h3>Further explanation
</h3>
Radioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles,
- alpha α particles ₂He⁴
- beta β ₋₁e⁰ particles
- gamma particles γ
- positron particles ₁e⁰
O-15 emits positron particles ₁e⁰, so the atomic number decreases by 1, the mass number is the same
Reaction

The mass number of the daughter isotope = 15, atomic number = 7
If we look at the periodic system, the element with atomic number 7 is Nitrogen (N)
I am pretty sure the answer is . But I might be wrong.
The atomic mass is greater than the atomic number.
Answer:
A=covalent B=low melting point
Explanation:
just did this on edge... not sure if it is still needed but there wasn't an answer so :)
The molar mass of Calcium hydroxide is 74 g/mol
To find the percent composition we have to find the number of atoms of each element in the formula .
So there’s
Calcium - 1
Oxygen - 2
Hydrogen - 2
Then have to multiply the relative atomic mass of each element by the number of atoms
Ca - 40 g/mol x 1 = 40
O - 16 g/mol x 2 = 32
H - 1 g/mol x 2 = 2
Then To find percent composition of each element we have to divide the mass of each element in the formula by the relative molecular mass of calcium hydroxide
Ca - 40 / 74 x 100 % = 54.0%
O - 32 / 74 x 100 % = 43.2 %
H - 2 / 74 x 100 % = 2.7%
From the options given correct answer is 3rd option
54.0% Ca , 43.0% O and 2.7 % H