Subatomic particles and the nuclear atomIB MYP Chemistry: Mind map

Exam questions on Subatomic particles and the nuclear atom

1. A school technician is making a poster about the particles inside a carbon atom. The poster must show students the three types of subatomic particle, where each one is found in the atom, and how their masses and charges compare.
   Describe the relative mass and relative charge of a proton and of an electron.2 marks
2. In 1911 a team of scientists fired a beam of positively charged alpha particles at a very thin sheet of gold foil and used a detector to record where the particles ended up. Before this, many scientists pictured the atom as a ball of positive charge with tiny electrons scattered through it. The team found that nearly all the alpha particles passed straight through the foil, a small number were deflected through large angles, and a very few bounced almost straight back.
   Explain why most alpha particles passed straight through the foil but a very few bounced back.2 marks
3. A science teacher is preparing a lesson on a lithium atom, which contains 3 protons, 4 neutrons and 3 electrons. She also wants to show how scientists' ideas about the atom changed between the early 1800s and the early 1900s. Students may use the fact that protons and neutrons have a relative mass of 1 and that an electron has a negligible relative mass.
   Explain why a lithium atom has no overall charge and why almost all of its mass is in the nucleus.3 marks