Question

go down to \show\ and select the option \stable/unstable\ and select the green plus symbol next to \mass number\. using the simulation, build the stable & neutral atoms for the following elements and record the data in the table below.

based on the data above, what particle determines the identity of the element?

what is the difference between atomic number and mass number? explain in complete sentences.

bonus! what would the mass number be of an element with 30 protons, 27 neutrons, and 30 electrons? how do you know?

hypothesize! what particles have to be balanced - equal to each other - in order to make a neutral atom? why?

Explanation:

• Atomic Number vs Mass Number:
• The atomic number is the number of protons in an atom. It determines the element's identity (e.g., helium has atomic number 2).
• The mass number is the sum of protons and neutrons in an atom (e.g., for helium in the table, \(2 + 1=3\)).
• Bonus Question:
• The mass number formula is \(Mass\ Number=Protons + Neutrons\). Given \(30\) protons and \(27\) neutrons, \(Mass\ Number = 30+27 = 57\).
• Neutral Atom Particles:
• Protons (positively - charged) and electrons (negatively - charged) must be balanced. A neutral atom has no overall charge, so the positive charge from protons (\(+1\) per proton) must cancel the negative charge from electrons (\(-1\) per electron).

Answer:

• Atomic Number vs Mass Number: The atomic number is the count of protons in an atom and defines the element. The mass number is the sum of protons and neutrons. For example, helium has an atomic number of 2 (from 2 protons) and a mass number of 3 (\(2\) protons \(+ 1\) neutron).
• Bonus: The mass number is \(57\). Using the formula \(Mass\ Number=Protons + Neutrons\), substituting \(30\) (protons) and \(27\) (neutrons) gives \(30 + 27=57\).
• Neutral Atom: Protons and electrons must be balanced. A proton has a \(+1\) charge and an electron has a \(-1\) charge. For an atom to be neutral (no net charge), the number of protons (\(+1\) charges) must equal the number of electrons (\(-1\) charges).