who discovered the nucleus of an atom? * (0.5 points)\ndalton\nthompson\nrutherford\nchadwick\n16\nhow many…

who discovered the nucleus of an atom? * (0.5 points)\ndalton\nthompson\nrutherford\nchadwick\n16\nhow many electrons are in the iron (iii) ion? * (0.5 points)\nenter your answer\n17\nhow many protons are in the uranium - 231 isotope? * (0.5 points)\nenter your answer
Answer
Explanation:
Step1: Recall atom - nucleus discovery
Ernest Rutherford discovered the nucleus of an atom through his gold - foil experiment.
Step2: Determine electrons in iron(III) ion
Iron (Fe) has an atomic number of 26, meaning a neutral Fe atom has 26 electrons. An iron(III) ion ($Fe^{3 + }$) has lost 3 electrons. So, $26−3 = 23$ electrons.
Step3: Find protons in uranium - 231 isotope
The atomic number of uranium (U) is 92. The number of protons in an isotope is equal to its atomic number. So, uranium - 231 has 92 protons.
Answer:
- C. Rutherford
- 23
- 92