Question

answer the questions about the following isotope $^{238}u^{+2}$
the atomic number, the number of protons, is 1
the mass number, the number of nucleons, is 2
the number of neutrons is 3
the number of electrons is 4
the charge is 5 making it an 6
a. 0 b. 1 c. 2 d. 3 e. 4 f. -1 g. -2
h. -3 i. -4 j. 238 k. 92 l 90 m. 146 n. element
o. anion p. cation

Explanation:

Step1: Identify atomic number

Uranium (U) has an atomic number of 92, which is the number of protons. So for the atomic - number question, the answer is 92.

Step2: Identify mass number

The isotope is written as $^{238}U^{ + 2}$, and the mass number is 238, which is the number of nucleons (protons + neutrons).

Step3: Calculate number of neutrons

The number of neutrons = mass number - atomic number. So, $238−92 = 146$.

Step4: Calculate number of electrons

A neutral uranium atom has 92 electrons. Since this is a $U^{+2}$ ion, it has lost 2 electrons. So the number of electrons is $92 - 2=90$.

Step5: Identify charge

The ion is $U^{+2}$, so the charge is + 2.

Step6: Identify ion type

A positively - charged ion is called a cation.

Answer:

1. K. 92
2. J. 238
3. M. 146
4. L. 90
5. C. 2
6. P. cation