Question
Which of the following pairs would be called isotopes?
A. Uranium-235 and uranium-238
B. Uranium-235 and plutonium-239
C. Sulfur-32 and phosphorus-32
D. hydrogen-1 and helium-4
A. Uranium-235 and uranium-238
B. Uranium-235 and plutonium-239
C. Sulfur-32 and phosphorus-32
D. hydrogen-1 and helium-4
Answers
GPT-4o mini
Isotopes are variants of a particular chemical element that have the same number of protons but different numbers of neutrons, resulting in different atomic masses.
From the options provided:
A. **Uranium-235 and uranium-238** - These are isotopes of uranium because they have the same number of protons (92) but different numbers of neutrons (143 and 146, respectively).
B. **Uranium-235 and plutonium-239** - These are not isotopes because they are different elements (uranium and plutonium).
C. **Sulfur-32 and phosphorus-32** - These are not isotopes because sulfur and phosphorus are different elements.
D. **Hydrogen-1 and helium-4** - These are not isotopes because they are different elements (hydrogen and helium).
The correct answer is **A. Uranium-235 and uranium-238**.
From the options provided:
A. **Uranium-235 and uranium-238** - These are isotopes of uranium because they have the same number of protons (92) but different numbers of neutrons (143 and 146, respectively).
B. **Uranium-235 and plutonium-239** - These are not isotopes because they are different elements (uranium and plutonium).
C. **Sulfur-32 and phosphorus-32** - These are not isotopes because sulfur and phosphorus are different elements.
D. **Hydrogen-1 and helium-4** - These are not isotopes because they are different elements (hydrogen and helium).
The correct answer is **A. Uranium-235 and uranium-238**.