Question

ions

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introduction: some of the particles that make up atoms have an electrical charge. electrons are negatively charged, while protons are positively charged. particles with opposite charges (+ and -) attract, while particles with the same charge (+ and + or - and -) repel.
question: what happens when atoms gain or lose electrons?

1. count: electrons move around the nucleus of atoms in specific shells, shown by the rings around the atoms in the gizmo. the first ring holds two electrons, and the second holds eight. (if you like, you can hide the inner electrons by selecting hide inner electrons.)

a. observe the sodium and chlorine atoms. how many electrons are there total in each atom?
sodium: chlorine:
b. each atom is neutrally charged, which means that each atom has the same number of protons and electrons. based on this, how many protons are in each atom?
sodium: chlorine:

1. observe: most atoms are stable with a configuration of eight valence electrons. this is known as the octet rule. how many valence electrons does each atom have?

sodium: chlorine:
form a bond: each electron has a charge of 1-, and each proton has a charge of 1+. you can calculate the charge of an atom by subtracting the number of electrons from the number of protons. move an electron from the sodium to the chlorine atom.
a. what are the charges of each atom now? sodium: chlorine:
turn on show charge to check. these charged atoms are called ions.
b. is each ion stable? explain.
click check in the lower right corner of the gizmo to check.

1. think and discuss: why is there an attraction between the two ions in this chemical bond?

Explanation:

Step1: Determine electron - proton numbers

Sodium (Na) has an atomic number of 11. In a neutral atom, the number of electrons equals the number of protons. So, the number of electrons and protons in a sodium atom is 11. Chlorine (Cl) has an atomic number of 17. So, the number of electrons and protons in a chlorine atom is 17.
Sodium: 11, Chlorine: 17

Step2: Find valence electrons

Sodium has an electron - configuration of 2, 8, 1. So, the number of valence electrons in sodium is 1. Chlorine has an electron - configuration of 2, 8, 7. So, the number of valence electrons in chlorine is 7.
Sodium: 1, Chlorine: 7

Step3: Calculate charges after electron transfer

When an electron is moved from sodium to chlorine:
Sodium loses one electron. Initially, it had 11 protons and 11 electrons. Now it has 11 protons and 10 electrons. The charge of sodium is \(11-(10)= + 1\).
Chlorine gains one electron. Initially, it had 17 protons and 17 electrons. Now it has 17 protons and 18 electrons. The charge of chlorine is \(17 - 18=-1\).
Sodium: + 1, Chlorine: - 1

Step4: Determine ion stability

Sodium ion (\(Na^+\)) has a full outer - shell configuration (2, 8). Chlorine ion (\(Cl^-\)) also has a full outer - shell configuration (2, 8, 8). According to the octet rule, both ions are stable as they have a stable electron configuration with eight valence electrons in their outer shell.

Answer:

1. A. Sodium: 11, Chlorine: 17

B. Sodium: 11, Chlorine: 17

1. Sodium: 1, Chlorine: 7
2. A. Sodium: + 1, Chlorine: - 1

B. Both ions are stable. Sodium ion has a full outer - shell of 8 electrons (2, 8) and chlorine ion has a full outer - shell of 8 electrons (2, 8, 8) following the octet rule.

1. There is an attraction between the two ions in this chemical bond because sodium ion (\(Na^+\)) is positively charged and chlorine ion (\(Cl^-\)) is negatively charged. Oppositely charged particles attract each other according to the principle of electrostatics.