Isotopes

4a. How many protons are in all Chlorine (Cl) atoms?

17

5b. Why is this number called a "mass" number?

Because protons and neutrons have a weight, electrons don't.

9. Write the name of the atom (similar to those in Model 1) for each of the atoms in question 6.

Boron-11 Flourine-16

3a. What whole model shown in Model 1 for each element is also found in the periodic table for that element?

Hydrogen - 1 carbon - 6 magnesium - 12

4b. A student says "I think that some chlorine atoms have 16 protons." Explain why this student is not correct.

It's not chlorine, that is now a different element.

7b. How is the mass number of an isotope expressed in the name of an atom?

It's the atom name-mass

3c. Refer to the isotope symbols in Model 1. Relative to the atomic symbol (H, C, or Mg), where is the atomic number located in the isotope symbol?

It's the bottom number out of the fraction

5a. How is the mass number determined?

Neutrons+protons=mass

3b. The whole number in each box of the periodic table is the atomic number of the element. What else does the atomic number of an element represent?

The protons

7a. Which corner of the isotope symbol contains the mass number?

The top number

11a. Do all isotopes of an element have the same atomic number? Give at least one example or counter-example from Model 1 that supports your answer.

Yes, because the atomic number can't change or it's a different element. For instance, Carbon is Carbon-6 as the atomic number at the time.