Question

Complete the following table with the appropriate data for each isotope given (all are neutral atoms): $$ \begin{array}{|c|c|c|c|c|c|c|} \hline \text { Element } & \text { Symbol } & \text { Atomic number } & \text { Mass number } & \text { Number of protons } & \text { Number of neutrons } & \text { Number of electrons } \\ \hline & { }^{134} \mathrm{Xe} & & & & & \\ \hline \text { Silver } & & & 107 & & & \\ \hline & & & & 9 & 10 & \\ \hline & & 92 & & & 143 & 92 \\ \hline & & & 41 & 19 & & \\ \hline \end{array} $$

Short answer

Xenon has atomic number 54, mass number 134, 54 protons, 80 neutrons, and 54 electrons. Silver has the atomic number 47, mass number 107, 47 protons, 60 neutrons, and 47 electrons. Fluorine has atomic number 9, 9 protons, and 19 neutrons. Uranium has 92 protons, 143 neutrons, and the mass number 235. Potassium has 19 protons, 22 neutrons, and mass number 41.

Step-by-step solution

Identify Isotope of Xenon

To find the atomic number, number of protons, and number of electrons for Xenon (Xe), use the mass number given and recall that the atomic number for Xenon is 54. Since it's a neutral atom, the number of protons equals the number of electrons, which are both 54, and the number of neutrons is the mass number minus the atomic number, which is 134 - 54.

Complete Silver Information

For Silver (Ag), the atomic number is 47. This number is also the number of protons and, because it is a neutral atom, the number of electrons. To find the number of neutrons, subtract the atomic number from the mass number: 107 - 47.

Determine Information for Unknown Element with 9 protons

The element with 9 protons is Fluorine (F), and its atomic number is 9. For a neutral atom, the number of electrons is also 9. The mass number is the sum of protons and neutrons, which is 9 + 10.

Fill in Data for Uranium Isotope

The element with the atomic number 92 is Uranium (U). For this isotope, since it is neutral, it has 92 electrons. The mass number can be determined by adding the number of protons (92) to the number of neutrons (143).

Find Information for Element with 19 Protons and Mass Number 41

The element with 19 protons is Potassium (K). Its atomic number is 19. The number of neutrons is calculated by subtracting the number of protons from the mass number: 41 - 19, and the number of electrons is 19.

Key concepts

Atomic Number

Understanding the atomic number is crucial when studying the periodic table and the elements. The atomic number, often denoted by the symbol 'Z', represents the total number of protons found in the nucleus of an atom. Each element is defined by its atomic number which is unique to that element—no two elements share the same atomic number. For instance, hydrogen, the simplest element, has an atomic number of 1 because it has one proton in its nucleus.

An atom is electrically neutral when the number of protons (positively charged) is equal to the number of electrons (negatively charged). So, if we know that an element is neutral and has an atomic number of 8, we can deduce that it must have 8 electrons. Atomic number is fundamental in not only distinguishing between elements but also in determining the element's position on the periodic table.

Mass Number

The mass number, symbolized by 'A', is another essential concept in the study of isotopes. It represents the total number of protons and neutrons in an atom's nucleus. Unlike the atomic number, the mass number is not fixed for a given element because an element can have various isotopes—atoms with the same number of protons but differing in the number of neutrons.

For example, look at carbon: it has an atomic number of 6, indicating 6 protons. But carbon can have mass numbers of 12 or 14, depending on whether there are 6 or 8 neutrons, respectively. When analyzing an unknown isotope, you can determine the mass number by adding the atomic number, which equates to the number of protons, to the number of neutrons. This sum gives you the mass number of that particular isotope.

Number of Neutrons

Neutrons, along with protons, make up the nucleus of an atom, and they play a pivotal role in stabilizing it. The number of neutrons in an atom can vary, even within atoms of the same element, resulting in different isotopes. The number of neutrons is not represented by any specific letter like protons (Z) or mass number (A), but it can be easily calculated. To find the number of neutrons, you subtract the atomic number from the mass number ((A - Z)).

For instance, if we take an isotope of neon with a mass number of 22 and an atomic number of 10, the calculation for the number of neutrons would be 22 - 10, giving us 12 neutrons. The variation in the number of neutrons among isotopes of the same element results in differences in mass but does not affect the chemical properties of the element.

Element Symbol Identification

Identifying an element symbol is a fundamental skill for working with the periodic table. The element symbol is usually a one- or two-letter abbreviation of the element's name, based on either its English name or its Latin name. For example, the symbol for hydrogen is 'H', and the symbol for gold is 'Au', from its Latin name 'Aurum'.

When approaching a table of isotopes, the symbols provide an immediate reference to the element in question. Atomic symbols also come in handy when depicting specific isotopes. The notation includes the element's symbol, the atomic number as a subscript, and the mass number as a superscript, for example, (^{14}_{6}C). This notation signifies the isotope of carbon that has 6 protons (atomic number) and a mass number of 14.