Question

examine the data table below and use the data to answer questions 5 - 9. note that the atom letters are random and not associated with atomic symbols for the elements.

atom	protons	neutrons	electrons
b	4	3	3
c	20	18	20
d	73	110	71
e	17	18	18

1. which atoms are isotopes of the same element?

a) atom a and atom e
b) atom a and atom c
c) atom c and atom e
d) no isotopes are shown in this table.

1. examine atom b. choose the appropriate identity:

a) lithium - 6
b) lithium - 7
c) beryllium - 6
d) beryllium - 7

for each of the questions below, list/bubble any and all atoms (a - e) that apply. this means you may have more than one answer for each question.

1. which atom(s) have a net negative charge?
2. which atom(s) are neutral in charge?

Explanation:

Step1: Recall isotope definition

Isotopes are atoms of the same element with different numbers of neutrons but the same number of protons. Atom A has 20 protons and atom C has 20 protons with different numbers of neutrons.

Step2: Recall atomic identity rule

The atomic number is equal to the number of protons. Atom B has 4 protons, and beryllium has an atomic number of 4. The mass - number is the sum of protons and neutrons, so for atom B, mass - number = 4 + 3=7.

Step3: Determine net charge

Net charge = number of protons - number of electrons. For atom A: 20 - 18 = + 2; for atom B: 4 - 3 = + 1; for atom C: 20 - 20 = 0; for atom D: 73-71 = + 2; for atom E: 17 - 18=-1.

Step4: Identify neutral atoms

Neutral atoms have equal number of protons and electrons. Atom C has 20 protons and 20 electrons, so it is neutral.

Answer:

1. b) Atom A and atom C
2. d) Beryllium - 7
3. E
4. C