Question
- The number of protons in an atom determines the identity of the atom. Atomic #= it Protons - In a neutral atom, the number of positive protons equals the number of negative electrons. # Protons = # Electrons - Protons and neutrons both have a mass of 1 amu. The mass of the electron is negligible compared to the mass of the proton and neutron. Thus, the mass number, or the mass of the atom, is the sum of the number of protons and neutrons. Mass # = Protons + # Neutrons Name & Symbol & Atomic # & Mass # & Protons & # Neutrons & #Electrons Selenium & & & & & 46 & & & & 222 & 86 & & & & & & & 118 & 79 & & 11 & & & 12 &
Answer
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Francis
Master · Tutor for 5 years
Answer
\begin{array}{|c|c|c|c|c|c|c|}\hline\ Name\ &\ Symbol\ &\ Atomic\ \#\ &\ Mass\ \#\ &\ \#\ Protons\ &\ \#\ Neutrons\ &\ \#\ Electrons\ \\\hline\ Selenium\ &\ Se\ &\ 34\ &\ 80\ &\ 34\ &\ 46\ &\ 34\ \\\hline\ Radon\ &\ Rn\ &\ 86\ &\ 222\ &\ 86\ &\ 136\ &\ 86\ \\\hline\ Gold\ &\ Au\ &\ 79\ &\ 197\ &\ 79\ &\ 118\ &\ 79\ \\\hline\ Sodium\ &\ Na\ &\ 11\ &\ 23\ &\ 11\ &\ 12\ &\ 11\ \\\hline\end{array}
Explanation
To fill in the missing values in the table, use the given relationships: 1. Atomic number equals the number of protons.2. In a neutral atom, the number of protons equals the number of electrons.3. Mass number equals the sum of protons and neutrons.