Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 5: Problem 4

Assuming that the valence shells of \(\mathrm{Li}\) and \(\mathrm{Be}\) are at approximately the same distance from their nuclei, explain how the core charges of \(\mathrm{Li}\) and \(\mathrm{Be}\) are consistent with the \(\mathrm{IE}_{1}\) values for \(\mathrm{Li}(0.52 \mathrm{MJ} / \mathrm{mole})\) and \(\mathrm{Be}(0.90 \mathrm{MJ} / \mathrm{mole})\).

Short Answer

Expert verified
Be requires more energy to remove an electron due to its higher core charge (more protons) compared to Li. Hence, the first ionization energy of Be is higher than that for Li. This reflects the stronger attraction of the electrons to the nucleus in Be than in Li.

Step by step solution

01

Understanding Atomic Structure of Li and Be

Lithium (Li), which is in the first group of the periodic table, has 3 protons and its outermost shell has 1 electron. Beryllium (Be), which is in the second group, has 4 protons and its outermost shell has 2 electrons. Therefore, even though both Li and Be have their valence electrons at approximately the same distance from the nucleus, Be has more protons than Li. This results in a stronger attraction for the electrons to the nucleus in Be.
02

Relating Atomic Structure to Ionization Energy

Ionization energy (IE₁) is the energy required to remove an electron from an atom. So, for Li, which has less protons and hence less core charge holding onto its valence electron, less energy is required to remove this electron. As opposed to Be, which has more protons causing a stronger attraction for the electrons, therefore a greater amount of energy is required to remove one of its entire shell electrons. That's why the IE₁ of Be (0.90 MJ/mole) is higher than the IE₁ for Li (0.52 MJ/mole).
03

Conclusion

The core charges of Li and Be are consistent with the given IE₁ values. This comes from the atomic difference in their structure. Be has more protons, meaning a stronger core charge attracts the electrons more strongly to the nucleus, hence requires more energy to remove an electron, showing its higher ionization energy. On the other hand, Li has fewer protons which cause weaker attraction towards the electrons, hence require less energy to remove an electron, showing its lower ionization energy.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

a) Based on its position in the periodic table, predict the valence shell, core charge, and number of valence electrons for \(\mathrm{Rb}\) and add these values to Table 1 . b) Using the shell model and referring to the Coulombic Potential Energy relationship (equation in Model 1, CA 3), explain clearly how the IE \(_{1}\) for \(\mathrm{Rb}\) is consistent with your answer to part a.

How does the core charge on a neutral atom change in moving from left to right across a row (period) of the periodic table?

Based on its position in the periodic table, what is the valence shell and what is the core charge for C? Explain your reasoning.

How does the core charge for Na compare to the core charge for \(\mathrm{Li} ?\)

Complete the following table: $$ \begin{array}{|c|c|c|c|c|} \hline \text { Atom } & \begin{array}{c} \text { Total number } \\ \text { of electrons } \end{array} & \begin{array}{c} \text { Number of } \\ \text { valence shell } \\ \text { electrons } \end{array} & \begin{array}{c} \text { Number of } \\ \text { inner shell } \\ \text { electrons } \end{array} & \text { Core Charge } \\ \hline \text { H } & 1 & & & \\ \hline \text { He } & & & & \\ \hline \text { Li } & & & & \\ \hline \end{array} $$
See all solutions

Recommended explanations on Chemistry Textbooks

Nuclear Chemistry

Read Explanation

Physical Chemistry

Read Explanation

The Earths Atmosphere

Read Explanation

Ionic and Molecular Compounds

Read Explanation

Chemical Reactions

Read Explanation

Organic Chemistry

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free