Question

part 2. procedure: 1. use the phet simulation, \build an atom.\ 2. check on the plus sign of the \mass number\ box. 3. add protons, neutrons, and electrons in the quantities indicated in each row of the data table. 4. record the missing information in each row. data table

number of protons	number of neutrons	number of electrons	name of the element	mass number
1	0	1	hydrogen
1	1	1	hydrogen
6	5	5
5	6	5

data analysis: 1. what affects the mass number of atoms? 2. write a math rule to determine the mass number of an atom: extension part 3: practice applying your understanding by playing 1st and 2nd levels on the game screen.

Explanation:

Step1: Recall mass - number formula

The mass number ($A$) of an atom is the sum of the number of protons ($p$) and neutrons ($n$), i.e., $A=p + n$. Electrons have negligible mass compared to protons and neutrons, so they do not affect the mass number.

Step2: Calculate mass numbers for each row in the table

For the first row: $p = 1$, $n=0$, so $A=1 + 0=1$.
For the second row: $p = 1$, $n = 0$, so $A=1+0 = 1$.
For the third row: $p = 1$, $n = 1$, so $A=1 + 1=2$.
For the fourth row: $p = 6$, $n = 5$, so $A=6 + 5=11$.
For the fifth row: $p = 5$, $n = 6$, so $A=5 + 6=11$.

Step3: Answer the data - analysis questions

1. The number of protons and neutrons affects the mass number of atoms. Since electrons have almost no mass, they do not contribute to the mass number.
2. The math rule to determine the mass number of an atom is $A=p + n$, where $A$ is the mass number, $p$ is the number of protons, and $n$ is the number of neutrons.

Answer:

Number of Protons	Number of Neutrons	Number of Electrons	Name of the Element	Mass Number
1	0	1	Hydrogen	1
1	1	1	Hydrogen	2
6	5	5	Carbon (assuming typical context, as 6 protons is carbon)	11
5	6	5	Boron	11

1. The number of protons and neutrons.
2. $A=p + n$