Question

1. based on your answers to #2 and #3, propose a definition for what an isotope is.
2. the average atomic mass of hydrogen is 1.008 amu. based on the hydrogen isotopes you have in your table, which isotope of hydrogen must be the most abundant? hydrogen - 1 because it is closest to the average
3. does the number of electrons affect the mass of the isotopes? why or why not?
4. how many neutrons does oxygen - 17 have?
5. cobalt - 60 is an isotope used as radiation therapy for cancer. how many protons and neutrons does cobalt - 60 have?
6. iodine - 131 is an isotope used to detect thyroid problems. how is iodine - 131 the same as iodine - 126?
7. can isotopes of different elements have the same mass? why or why not?

Explanation:

Question 4

Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons. This gives them different mass - numbers while maintaining the same chemical properties.

Question 6

The mass of an isotope is mainly determined by the number of protons and neutrons in the nucleus. Electrons have a very small mass (about 1/1836 of the mass of a proton or neutron), so the number of electrons does not significantly affect the mass of an isotope.

Question 8

Cobalt has an atomic number of 27. The number of protons is equal to the atomic number. For cobalt - 60, the number of protons is 27. The mass - number is 60. Using the formula Mass - number=Number of protons + Number of neutrons, the number of neutrons is 60 - 27=33.

Question 9

Iodine - 131 and iodine - 126 are isotopes of iodine. They have the same number of protons (since they are the same element, iodine, with an atomic number of 53), which means they have the same chemical properties.

Question 10

Isotopes of different elements can have the same mass. This is because the mass of an isotope is determined by the sum of protons and neutrons. For example, an isotope of one element with a certain combination of protons and neutrons can have the same mass as an isotope of another element with a different combination of protons and neutrons.

Answer:

1. Isotopes are atoms of the same element with the same number of protons but different numbers of neutrons.
2. No, because electrons have a very small mass compared to protons and neutrons.
3. 27 protons and 33 neutrons.
4. They have the same number of protons and thus the same chemical properties.
5. Yes, because the mass of an isotope depends on the sum of protons and neutrons and different combinations in different elements can result in the same mass.