Which of these statements regarding isotopes is not true?
A. Isotopes are atoms of the same element with different mass numbers.
B. Isotopes have the same number of protons and electrons in each atom, but a different number of neutrons in their nucleus.
C. Isotopes of an element have the same chemical and physical properties.
D. Radio-isotopes are isotopes with unstable nuclei that emit radiation.
Answer:C
Which of these statements regarding isotopes is not true?
A. Isotopes are atoms of the same element with different mass numbers. B. Isotopes have the same number of protons and electrons in each atom, but a different number of neutrons in their nucleus. C. Isotopes of an element have the same chemical and physical properties. D. Radio-isotopes are isotopes with unstable nuclei that emit radiation.
Explanation: Isotopes of an element have the same chemical properties, but they differ in a few physical properties such as density. (Note that you were looking for the answer choice that is not true and the rest of the choices are true.)