Question

1. fill in the blanks on the diagrams below.

1. explain how to find the atomic mass of an atom.

1. explain how to find the number of neutrons of an atom.

1. define the following terms:

atom:
ion:
isotope:

1. what particle is the same in an ion, isotope, and an atom of the same element?

1. fill in the table below, beware if ions and isotopes

symbol | protons | neutrons | electrons | atomic mass
zn-67 | | | |

24

56

$^{27}$al$^{3+}$ | | | |

5

5

zr-91 | | | |

na$^+$ | | | |
p$^{3-}$ | | | |

Explanation:

Step1: Fill periodic table blanks

For the first diagram:
Atomic Number = $11$
Atomic Mass = $22.98977$
For the right diagram:
Top left blank (Atomic Number): $11$
Top right blank (Atomic Mass): $22.98977$

Step2: Explain atomic mass calculation

Atomic mass is the weighted average of the masses of all naturally occurring isotopes of an element, calculated by:
$$\text{Atomic Mass} = \sum (\text{Isotope Mass} \times \text{Abundance})$$
where abundance is the decimal fraction of the isotope in nature.

Step3: Explain neutron count calculation

Neutrons = Atomic Mass (rounded to nearest whole number, mass number) - Atomic Number
$$\text{Neutrons} = A - Z$$
$A$ = mass number, $Z$ = atomic number

Step4: Define key terms

Atom: Neutral particle with equal protons/electrons.
Ion: Charged atom/molecule (unequal protons/electrons).
Isotope: Same element, different neutron count.

Step5: Identify shared particle

Protons determine element identity, so they are identical across ion, isotope, atom of the same element.

Step6: Fill the table

Row 1 (Zn-87):

Zn has atomic number 30 (protons=30). Neutrons = $87-30=57$. Neutral atom, electrons=30. Atomic Mass=87.

Row 2 (24 protons, mass 56):

Element is Cr (Z=24). Neutrons = $56-24=32$. Neutral atom, electrons=24. Symbol: Cr-56.

Row 3 ($^{27}\text{Al}^{3+}$):

Al has Z=13 (protons=13). Neutrons = $27-13=14$. $3+$ ion: electrons = $13-3=10$. Atomic Mass=27.

Row 4 (5 protons, 5 neutrons):

Element is B (Z=5). Mass = $5+5=10$. Neutral atom, electrons=5. Symbol: B-10.

Row 5 (Zr-91):

Zr has Z=40 (protons=40). Neutrons = $91-40=51$. Neutral atom, electrons=40. Atomic Mass=91.

Row 6 ($\text{Na}^+$):

Na has Z=11 (protons=11). Mass number 23, neutrons = $23-11=12$. $1+$ ion: electrons = $11-1=10$. Atomic Mass=22.99 (or 23).

Row 7 ($\text{P}^{3-}$):

P has Z=15 (protons=15). Mass number 31, neutrons = $31-15=16$. $3-$ ion: electrons = $15+3=18$. Atomic Mass=30.97 (or 31).

Answer:

1.
Left diagram:
Atomic Number = $11$
Atomic Mass = $22.98977$
Right diagram:
Top left blank: $11$
Top right blank: $22.98977$

1. Atomic mass is the weighted average of the masses of all naturally occurring isotopes of an element, calculated by multiplying each isotope's mass by its relative abundance (as a decimal) and summing these values.

1. Subtract the atomic number (number of protons) from the rounded atomic mass (mass number) of the atom: $\text{Neutrons} = \text{Mass Number} - \text{Atomic Number}$

4.
Atom: A neutral, basic unit of matter with equal numbers of protons and electrons.
Ion: A charged atom or molecule with an unequal number of protons and electrons.
Isotope: Atoms of the same element that have the same number of protons but a different number of neutrons.

1. Proton

6.

Symbol	Protons	Neutrons	Electrons	Atomic Mass
Cr-56	24	32	24	56
$^{27}\text{Al}^{3+}$	13	14	10	27
B-10	5	5	5	10
Zr-91	40	51	40	91
$\text{Na}^+$	11	12	10	23 (22.99)
$\text{P}^{3-}$	15	16	18	31 (30.97)