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Subtraction Word Problem
1) Here Is a Picture of the Three Isotopes of Carbon. Find Their Number of Neutrons.
The number of neutrons in the C-12 atom is
12 – 6 = 6
The number of neutrons in the C-13 atom is
13 – 6 = 7
The number of neutrons in the C-13 atom is
14 – 6 = 8
2) Nickel (Z = 28, a = 58) Has 30 Isotopes That Have the Same Atomic
Number. But Their Atomic Masses Range From a = 48 to a = 78. a) How Many Neutrons Does the Lightest Isotope of Nickel Have?
b) How Many Neutrons Does the Heaviest Isotope of Nickel Have?
- The lightest isotope of nickel has A = 48.
so, the number of neutrons = 48 – 28 = 20 - The heaviest isotope of nickel has A = 78
So, the number of neutrons = 48 – 78 = 30
3) Here Is a List of Isotopes of Plutonium. Find Their Number of Neutrons.
| Isotopes | Number of neutrons (N) |
|---|---|
| 228Pu94 | |
| 229Pu94 | |
| 232Pu94 | |
| 233Pu94 | |
| 234Pu94 | |
| 240Pu94 | |
| 241Pu94 | |
| 242Pu94 | |
| 243Pu94 | |
| 244Pu94 | |
| 245Pu94 | |
| 246Pu94 | |
| 247Pu94 |
| Isotopes | Number of neutrons (N) |
|---|---|
| 228Pu94 | N = 228 – 94 = 134 |
| 229Pu94 | N = 229 – 94 = 135 |
| 232Pu94 | N = 232 – 94 = 138 |
| 233Pu94 | N = 233 – 94 = 139 |
| 234Pu94 | N = 234 – 94 = 140 |
| 240Pu94 | N = 240 – 94 = 146 |
| 241Pu94 | N = 241 – 94 = 147 |
| 242Pu94 | N = 242 – 94 = 148 |
| 243Pu94 | N = 243 – 94 = 149 |
| 244Pu94 | N = 244 – 94 = 150 |
| 245Pu94 | N = 245 – 94 = 151 |
| 246Pu94 | N = 246 – 94 = 152 |
| 247Pu94 | N = 247 – 94 = 153 |
4) Here Is a List of Elements With Their Atomic Mass And Atomic Numbers. Find the Number of Neutrons of the Elements.
| Elements | Number of Neutrons |
|---|---|
| 98Tc43 | N = |
| 145Pm61 | N = |
| 209Po84 | N = |
| 210At85 | N = |
| 222Pn86 | N = |
| 227Ac89 | N = |
| 237Np93 | N = |
| 243Am95 | N = |
| 247Cm96 | N = |
| 247Bk97 | N = |
| 251Cf98 | N = |
| 257Fm100 | N = |
| 252Es99 | N = |
| 258Md101 | N = |
| 261Rf104 | N = |
| 259Tc102 | N = |
| 277Hs108 | N = |
| 266Sg106 | N = |
| Elements | Number of Neutrons |
|---|---|
| 98Tc43 | N = 98 – 43 = 55 |
| 145Pm61 | N = 145 – 61 = 84 |
| 209Po84 | N = 209 – 84 = 121 |
| 210At85 | N = 210 – 85 = 125 |
| 222Pn86 | N = 222 – 86 = 132 |
| 227Ac89 | N = 227 – 89 = 138 |
| 237Np93 | N = 237 – 93 = 144 |
| 243Am95 | N = 243 – 95 = 148 |
| 247Cm96 | N = 247 – 96 = 151 |
| 247Bk97 | N = 247 – 97 = 150 |
| 251Cf98 | N = 251 – 98 = 153 |
| 257Fm100 | N = 257 – 100 = 157 |
| 252Es99 | N = 252 – 99 = 153 |
| 258Md101 | N = 258 – 101 = 157 |
| 261Rf104 | N = 261 – 104 = 157 |
| 259Tc102 | N = 259 – 102 = 157 |
| 277Hs108 | N = 277 – 108 = 169 |
| 266Sg106 | N = 266 – 106 = 160 |
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