Q.What is the difference between an α - particle and helium atom?

Step 1. This chapter states directly that an alpha particle is identical with a helium nucleus, and is written using the same notation, 4-2-He.

Step 2. A helium nucleus (the alpha particle) consists of 2 protons and 2 neutrons bound together, with no electrons attached, so its net electric charge is +2 (from the 2 unbalanced protons).

Step 3. A neutral helium ATOM has that identical nucleus, but surrounded by 2 electrons occupying the space around it -- exactly enough negative charge to balance the nucleus's +2, making the atom as a whole electrically neutral. …

Compare the alpha particle's composition (bare nucleus) against a full helium atom's composition (nucleus + 2 ele …

• Saying the two are simply 'the same thing' without noting the missing electrons and resulting charge on the alpha particle. …