Question

how many protons are there in the isotope represented herein:
$_{31}^{50}x^{-6}$
81
31
6
19
37
50
56
8 multiple choice 10 points
how many electrons are there in $^{10}x^{+}$? take the number of neutrons to be 7.
7
2
1
10
6

Explanation:

Step1: Recall proton - atomic number relation

In the isotope notation $_{31}^{50}X^{- 6}$, the sub - script represents the atomic number. The number of protons in an atom is equal to its atomic number.

Step2: Identify the atomic number

The atomic number is 31, so the number of protons is 31.

Step1: Determine the atomic number

For the ion $^{10}X^{+}$, the mass number is 10. Given the number of neutrons is 7, we can find the atomic number (number of protons) using the formula $mass\ number=number\ of\ protons + number\ of\ neutrons$. So, number of protons $=10 - 7=3$.

Step2: Analyze the charge and electrons

A $+1$ charge means the atom has lost 1 electron. In a neutral atom, number of electrons = number of protons. For $X^{+}$ with 3 protons originally, the number of electrons is $3 - 1=2$.

Answer:

B. 31