| What are atoms? | The smallest particle to exist. |
| What is the radius of an atom? | 1 × 10⁻¹⁰ |
| What is ionisation? | It is creating an ion. This is when an atom loses or gains electrons. |
| What is excitation? | It is when an electron moves away from the nucleus because the atom has absorbed EM radiation. If enough is absorbed, the electron can leave the atom. |
| What is de-excitation? | It is when the electron goes down to a lower energy level and EM radiation is emitted. |
| What is an isotope? | An atom of an element with the same number of protons, but a different number of neutrons. |
| What is an alpha particle? | A particle with 2 protons and 2 neutrons. It's a helium nucleus. |
| What makes an atom radioactive? | If there are too many neutrons in the nucleus. |
| How can an atom become more stable? | If particles or waves of energy are released. |
| What is nuclear decay? | When an unstable isotope changes into a more stable isotope by releasing particles and energy in the form of radiation. |
| What is a beta particle? | A high speed electron thats ejected from the nucleus when a neutron becomes a proton and an electron. |
| What is gamma? | A high frequency EM radiation. |
| What is the relative mass of alpha? | 4. |
| What is the relative mass of beta? | 1/2000 |
| What is the relative mass of gamma? | 0. |
| What is the relative charge of alpha? | +2. |
| What is the relative charge of beta? | -1. |
| What is the relative charge of gamma? | 0. |
| What are alpha particles range in the air? | 5cm. |
| What are beta particles range in the air? | 1 metre. |
| What is the range of gamma radiation in the air? | Infinite. |
| What is the penetrating power of alpha? | It's absorbed by paper. |
| What is the penetrating power of beta? | It's absorbed by aluminium. |
| What is the penetrating power of gamma? | It's absorbed by several mm of lead or several m of concrete. |
| What is the ionising power of alpha? | It is the most ionising. |
| What is the ionising power of beta? | It is slightly ionising. |
| What is the ionising power of gamma? | It is the least ionising |
| What is the motion of alpha in an electric field? | It is weakly deflected to the negative plate. |
| What is the motion of beta in an electric field? | It is strongly deflected to the positive plate. |
| What is the motion of gamma in an electric field? | There is no effect. |
| What is transmutation? | It is when an atom of an element changes into another element because of nuclear decay. |
| What is the formula for alpha decay? | ᴬ ₓX → ᴬ⁻⁴ ₓ₋₂ Y + ⁴ ₂He |
| What is the formula for beta decay? | ᴬ ₓX → ᴬ⁻⁴ ₓ₊₁ Y + ⁰ ₁e |
| What is neutron emmision? | The way a nuclei stabilises itself by releasing a neutron. |
| What is the geiger-muller tube? | A detector that counts the count-rate. |
| What is activity? | The rate at which a source of unstable nuclei decays. Its measured in becquerel (Bq). |
| What is count rate? | The number of decays recorded each second by a detector. |
| What is a radio isotope? | An atom of an element that's unstable. |
| How do paper mills use beta particles? | They work by having a beta source emitting radiation.
Between the source and the detector is paper.
If the number on the detector increases, the paper is getting too thin, and if the number on the detector decreases, the paper is getting too thick.
It ensures that the paper has the right thickness.
It also works with aluminium. |
| How do smoke alarms use alpha particles? | Smoke alarms send out radiation into the gap in between the smoke detectors in the aim.
It then ionizes the air creating current.
When the smoke rises, it absorbs the ions and opens up the gap again, setting off the alarm because the current is gone. |
| How is beta and gamma radiation used in medicine? | Beta and gamma radiation is ejected through someone to detect illnesses or damaged organs, and kill cancerous cells.
Because it is so penetrating, it can easily pass through the human body, and because they both aren't that ionising, it's safe to use. |
| What is carbon dating? | An application of half lives. |
| What is the half life of a radioactive isotope? | The time it takes for the number of nuclei of the isotope to half. |
| What is irridaition? | When an object or a person is exposed to nuclear radiation. |
| What is contamination? | When unwanted radioactive atoms go on or in an object or person. |
| What is peer review? | When other scientists check someone else's work to validate it and ensure it's not bias. |
| How can we use graphs to show half lives? | The graph shows activity against time, and you can find the half life by finding the time interval on the x-axis, corresponding to to half of the activity on the y-axis. |
| What are half lives? | The time taken for the number of radioactive nuclei in an isotope to halve. |
