Question

Fill in the gaps in the following table, assuming each column represents a neutral atom. $$ \begin{array}{l|c|c|c|c|c} \hline \text { Symbol } & { }^{159} \mathrm{~Tb} & & & & \\ \text { Protons } & & 29 & & & 37 \\ \text { Neutrons } & & 34 & 53 & & \\ \text { Electrons } & & & 42 & 34 & \\ \text { Mass no. } & & & & 79 & 85 \\ \hline \end{array} $$

Short answer

}}\mathrm{Cu} & & {}^{\mathrm{?}}\mathrm{Se} & { }^{85} \mathrm{Rb} \\ \text { Protons } & 65 & 29 & & 34 & 37 \\ \text { Neutrons } & 94 & & 53 & & 48 \\ \text { Electrons } & 65 & 29 & 42 & 34 & 37 \\ \text { Mass no. } & 159 & & & & 85 \\ \hline \end{array} $$

Step-by-step solution

Identify the given information for each atom

The table has the following information given: $$ \begin{array}{l|c|c|c|c|c} \hline \text { Symbol } & { }^{159} \mathrm{Tb} & & & & \\ \text { Protons } & & 29 & & & 37 \\ \text { Neutrons } & & 34 & 53 & & \\ \text { Electrons } & & & 42 & 34 & \\ \text { Mass no. } & & & & 79 & 85 \\ \hline \end{array} $$ Next, we will fill the table by deriving the information for each atom using the relationships mentioned above.

Derive the information for each atom using the relationships

Let's start with the first atom \({ }^{159}\mathrm{Tb}\): Number of protons (\(p\)): Tb is Terbium, which has 65 protons. Number of neutrons (\(n\)): Using the relationship \(A = p + n\), we get \(n = A - p = 159 - 65 = 94\). Number of electrons (\(e\)): In a neutral atom, the number of electrons equals the number of protons, so \(e = p = 65\). Moving on to the second atom with 29 protons: Symbol: The element with 29 protons is Copper (Cu). Number of neutrons (\(n\)): We do not have enough information to calculate this. Number of electrons (\(e\)): Since it is a neutral atom, e = p = 29. Mass number (\(A\)): We do not have enough information to calculate this. For the third atom with 53 neutrons: (Symbol, Number of protons, and Mass number: We do not have enough information to calculate these) Number of electrons (\(e\)): We have 42 electrons. Now for the fourth atom with 34 electrons: Symbol: Since we know (from Step 3) that atomic number = number of protons, we can conclude that this atom has 34 protons, which means it is Selenium (Se). Number of protons (\(p\)): Since it's a neutral atom, p = e = 34. Number of neutrons (\(n\)): We do not have enough information to calculate this. Mass number (\(A\)): We do not have enough information to calculate this. Finally, for the fifth atom with 37 protons: Symbol: The element with 37 protons is Rubidium (Rb) Number of neutrons (\(n\)): Using the relationship \(A = p + n\), we get \(n = A - p = 85 - 37 = 48\). Number of electrons (\(e\)): Since it is a neutral atom, e = p = 37. Mass number (\(A\)): The given mass number is 85. Now we can fill in the table with the derived information.

Fill in the table with the derived information

After deriving the information, we can fill in the table: $$ \begin{array}{l|c|c|c|c|c} \hline \text { Symbol } & { }^{159} \mathrm{Tb} & {}^{\mathrm{?}}\mathrm{Cu} & & {}^{\mathrm{?}}\mathrm{Se} & { }^{85} \mathrm{Rb} \\ \text { Protons } & 65 & 29 & & 34 & 37 \\ \text { Neutrons } & 94 & & 53 & & 48 \\ \text { Electrons } & 65 & 29 & 42 & 34 & 37 \\ \text { Mass no. } & 159 & & & & 85 \\ \hline \end{array} $$ As seen in the table above, we have filled all the possible gaps with the given information.