Video Transcript
The stability of a covalent bond depends on the balance of attractive and repulsive forces between the electrons and nuclei of the bonding atoms. Which of the following is an accurate description of the attractive and repulsive forces in a covalent bond? (A) Electrons are repelled by the nucleus and by each other. (B) Electrons are attracted to the nucleus and repelled by each other. (C) Electrons are attracted to the nucleus and to each other. (D) Electrons are repelled by the nucleus and attracted to each other.
The key to this problem lies in understanding that like charges tend to repel each other, while oppositely charged particles tend to attract each other. Covalent bonds are formed between two atoms which are typically both nonmetals. Each atom contains a positively charged nucleus surrounded by negatively charged electrons. The nuclei are both positively charged, so they repel each other. The electrons also repel each other as they’re both negatively charged. However, the nuclei and the electrons have opposite charges. So the positively charged nucleus of one atom will be attracted to the negatively charged electrons in the other atom. So the answer choice that is an accurate description of the attractive and repulsive forces in a covalent bond is answer choice (B). Electrons are attracted to the nucleus and repelled by each other.
Which particles interact to produce the force of attraction between atoms in a covalent bond?
As we just discussed, in a covalent bond, the positively charged nucleus in one atom is attracted to the negatively charged electrons in another atom. This is responsible for the force of attraction between atoms. But the question specifically asked, which particles are attracted to each other? And the nucleus isn’t really a particle, as the nucleus is made up of smaller particles, the positively charged proton and the uncharged neutron. So the electrons of one atom are attracted to the protons that are in the nucleus of the other atom.
So the particles that interact to produce the force of attraction between atoms in a covalent bond are protons and electrons.
