Which of the following statements are correct, when referring to an at

1.	Which of the following statements are correct, when referring to an atom? a. The valence shell is responsible for radioactivity b. Radioactivity results from an imbalance in the number of protons and electrons c. All atoms have an equal number of protons and neutrons d. Neutrons have a negative charge e. Radon contributes to our background radiation
Answer» a. False. The valence shell is the outer electron shell and influences the chemical and thermal properties of an atom. Radioactivity involves the nucleus. b. False. Radioactivity occurs as a result of unstable nuclei (radio nuclide) that have an excess or deficit of neutrons. c. False. For example, hydrogen has one proton only and no neutrons. d. False. Neutrons have no charge. Protons have a positive charge and electrons have a negative charge. e. True. Radon is an example of a naturally occurring radio nuclide.

Which of the following statements are correct, when referring to an atom? a. The valence shell is responsible for radioactivity b. Radioactivity results from an imbalance in the number of protons and electrons c. All atoms have an equal number of protons and neutrons d. Neutrons have a negative charge e. Radon contributes to our background radiation

Answer»

a. False. The valence shell is the outer electron shell and influences the chemical and thermal properties of an atom. Radioactivity involves the nucleus.

b. False. Radioactivity occurs as a result of unstable nuclei (radio nuclide) that have an excess or deficit of neutrons.

c. False. For example, hydrogen has one proton only and no neutrons.

d. False. Neutrons have no charge. Protons have a positive charge and electrons have a negative charge.

e. True. Radon is an example of a naturally occurring radio nuclide.

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