an atomic physicist determines that an atom is composed of 8 positively charged particles and has a mass of…
an atomic physicist determines that an atom is composed of 8 positively charged particles and has a mass of 15 amu. which is the best conclusion that can be drawn?\nthe atom has 7 neutrons and 8 protons.\nthe atom has 7 electrons and 8 protons.\nthe atom has 8 neutrons and 7 electrons.\nthe atom has 8 electrons and 7 protons.
Answer
Explanation:
Step1: Identify positively - charged particles
Positively - charged particles in an atom are protons. Given there are 8 positively - charged particles, so the number of protons $p = 8$.
Step2: Recall mass number formula
The mass number $A$ of an atom is the sum of the number of protons and neutrons, i.e., $A=p + n$, where $A$ is the mass number, $p$ is the number of protons, and $n$ is the number of neutrons. Given $A = 15$ and $p = 8$.
Step3: Calculate number of neutrons
We can find the number of neutrons $n$ by rearranging the formula $n=A - p$. Substituting $A = 15$ and $p = 8$ into the formula, we get $n=15 - 8=7$. Electrons have negligible mass compared to protons and neutrons and are not considered in mass - number calculations.
Answer:
The atom has 7 neutrons and 8 protons.