Physical Week 1 Flashcards
Amount of substance and Atomic Structure
How many electrons are in a neutral atom?
Electrons in a neutral atom are equal to the number of protons.
What are isotopes?
Isotopes are atoms with the same atomic number but different mass numbers, and they have the same number of protons but different numbers of neutrons.
What happens to the movement of sub-atomic particles when they share the same speeds?
Electrons curve towards the positive plate, protons curve towards the negative plate, and neutrons continue moving straight ahead.
How are electrons accelerated and what determines their kinetic energy?
Electrons are accelerated by an electric field, and their kinetic energy is determined by their mass and velocity.
How can the time taken for a specific ion to travel along the flight tube be calculated?
The time taken for a specific ion to travel along the flight tube can be calculated using the length of the tube and the ion’s velocity.
How can ions with different mass-to-charge ratios be distinguished in a flight tube?
Ions with different mass-to-charge ratios have the same kinetic energy but different velocities in a flight tube. The flight times of ions in the tube can be used to distinguish them.
How do protons, electrons, and neutrons behave in electric fields?
Protons curve towards the negative plate, electrons curve towards the positive plate, and neutrons continue straight ahead.
What is the difference between electron impact and electrospray ionization in a mass spectrometer?
Electron impact is suitable for elements and light substances and can fragment larger molecules, while electrospray ionization is used for larger organic molecules and prevents fragmentation under gentle operating conditions.
What is involved in the detection of sub-atomic particles?
The detection of sub-atomic particles involves measuring the mass/charge ratio and abundance of ions using a current generated by the transfer of electrons.
If a beam of electrons, protons, and neutrons with the same speed is directed towards a plate with a positive charge on one side and a negative charge on the other, how will each particle behave?
Electrons will curve towards the positive plate, protons will curve towards the negative plate, and neutrons will continue moving straight ahead.
How can the relative atomic mass of an element be calculated?
The relative atomic mass of an element can be calculated using the abundance data of its isotopes.
What is the composition of the nucleus of an atom?
The nucleus of an atom contains protons and neutrons.
What is the mass number?
The mass number of an atom is equal to the sum of the number of protons and the number of neutrons it has. It is also known as the nucleon number.
What is the atomic number?
The atomic number of an atom is equal to the number of protons it has. It is also known as the proton number.
What happens during detection (TOF)?
In a mass spectrometer, detection refers to the process of measuring the abundance of ions and their mass-to-charge ratios. The current generated by the ions reaching the detector is analyzed by a computer.
Define relative atomic mass.
The average mass of one atom of an element, relative to 1/12 of an atom of carbon-12.
What is the complexity of the electronic structure of d-block elements?
The electronic structure of d-block elements is complex, with some debate about the filling order of 4s and 3d subshells.
What is the basis for dividing the periodic table into blocks?
The periodic table is divided into blocks based on the type of subshell being filled.
How is the electron configuration of atoms determined?
The electron configuration of atoms is determined by the principle energy levels, sub energy levels, and orbitals, with atoms filling subshells by energy level and each orbital holding up to 2 electrons of opposite spin.
Why does the small drop from phosphorus to sulfur occur in terms of ionization energy?
The small drop from phosphorus to sulfur occurs because sulfur’s 4th electron enters the already filled 3p orbital, resulting in repulsion and making the second electron easier to remove.
What factors influence ionization energies?
Ionization energies are influenced by factors such as nuclear attraction, electron distance from the nucleus, and shielding.
Why does sodium have a lower first ionization energy than neon?
Sodium has a lower first ionization energy than neon because its outer electron is in a more shielded, distant 3s shell, making it easier to remove.
What pattern emerges when observing the second ionization energy for each element?
When observing the second ionization energy for each element, a pattern similar to the first ionization energy emerges, but with all elements shifted one step to the left. Group 1 elements now occupy the peaks in the graph.
Why does Lithium have the second-highest ionisation energy among all elements?
Its second electron is removed from the first 1s shell, closest to the nucleus, with no shielding from inner shells and it has more protons than Helium.
