Question

how many electrons are there in 10x+? take the number of neutrons to be 7. 7 2 1 10 6 9

Explanation:

Step1: Determine the atomic number

The mass - number of the ion is 10 and the number of neutrons is 7. Using the formula $A = Z+N$ (where $A$ is the mass - number, $Z$ is the atomic number, and $N$ is the number of neutrons), we can find the atomic number $Z=A - N$. So, $Z = 10 - 7=3$.

Step2: Analyze the ion charge

The ion is $X^{+}$, which means it has lost 1 electron. For a neutral atom, the number of electrons is equal to the atomic number. For the ion $X^{+}$, the number of electrons $e=Z - 1$. Substituting $Z = 3$ into the formula, we get $e=3 - 1 = 2$.

Answer:

2