The nuclear atom - IB DP Chemistry Study Notes - New Syllabus 2025
Introduction to the Particulate Nature of Matter – Study Notes
IITian Academy excellent Introduction to the Particulate Nature of Matter – Study Notes and effective strategies will help you prepare for your IB DP Chemistry SL 2025 exam.
- IB DP Chemistry 2025 SL- IB Style Practice Questions with Answer-Topic Wise-Paper 1
- IB DP Chemistry 2025 SL- IB Style Practice Questions with Answer-Topic Wise-Paper 2
- IB DP Chemistry 2025 HL- IB Style Practice Questions with Answer-Topic Wise-Paper 1
- IB DP Chemistry 2025 HL- IB Style Practice Questions with Answer-Topic Wise-Paper 2
S1.2.1 – The Nucleus
What did Rutherford’s work tell us?
- He found that the atom is mostly empty space
- Nearly all of its mass was concentrated in a tiny central nucleus
How can we represent the composition of an Atom and Nuclear Notation for an Ion?
S1.2.2 – Isotopes
What are isotopes?
- Members of a family of the same element
- They have the same number of protons but different numbers of neutrons.
Chemical Properties of Isotopes:
- Isotopes of the same element have almost identical chemical properties.
- This is because the only difference between them is the amount of neutrons.
- Same chemical properties but different physical properties.
- For example, the boiling points are different
Notation used in the Periodic Table:
Relative Atomic Mass (Ar) using % Abundance Data:
Ar = (35×0.75) + (37×0.25)
= 26.25 + 9.25
Ar = 35.5
S1.2.3 – [HL] Mass Spectra
How do we identify isotopes and their abundance?
- Using mass spectrometry, we can determine the relative abundance of each isotope.
The Mass Spectrometer:
- A sample is injected into the spectrometer and heated under high temperature
- The ions will speed up while sending them into two strong magnets which deflect them based on their mass (low mass, more deflection)
- Using the deflections, we can determine the isotope’s abundance.
Calculate the relative atomic mass (Ar) of Magnesium:
Ar = ((24×0.79)+(25×0.10)+(26×0.11))
= (18.96+2.50+2.86)
Ar = 24.32
S1.2.4 – Question & Review
How do the Nuclei of Atoms Differ?
-Similarities Between all Nuclei- | -Differences between the Nuclei of Different Elements |
– They are very dense and extremely small – Contain 99.9% of the mass of an atom and are ten thousand times smaller than an atom | 1. Number of Protons and Neutrons: The nuclei of different elements have varying numbers of protons and neutrons. The number of protons determines the element’s atomic number, while the sum of protons and neutrons gives the atomic mass. In general, the number of protons in the nucleus is equal to the atomic number of the element, while the number of neutrons can vary within isotopes of the same element 2- Size : The size of a nucleus can vary depending on the element. The size of the nucleus is determined by the number of protons and neutrons it contains. |
Retrieval Practice: