Question

t/f if false, make the statement true

1. the difference between carbon - 12 and carbon - 13 is the number of electrons.
2. all isotopes of an element have the same chemical properties.
3. an atom is electrically neutral if it has the same number of neutrons and protons.
4. most of the mass of an atom resides in the electron cloud and most of the volume of an atom

resides in the nucleus.

1. electrons are the largest and heaviest subatomic particle.
2. electrons and protons have essentially the same mass.
3. all isotopes have the same mass number
4. 1 amu = 1/12 the mass of a carbon - 14 atom
5. the nucleus of an atom has a net positive charge.
6. carbon - 14 has an atomic number of 14 and has 14 protons.

Explanation:

1. Carbon - 12 and carbon - 13 are isotopes. Isotopes differ in the number of neutrons, not electrons.
2. Isotopes have the same number of protons and electrons (for neutral atoms), so they have the same chemical properties.
3. An atom is electrically neutral if it has the same number of protons and electrons. Neutrons have no charge.
4. Most of the mass of an atom is in the nucleus (protons and neutrons), and most of the volume is in the electron cloud.
5. Electrons are the smallest and lightest subatomic particles. Protons and neutrons are larger and heavier.
6. Protons are much heavier than electrons. The mass of a proton is about 1836 times the mass of an electron.
7. Isotopes have different mass numbers (sum of protons and neutrons) because they have different numbers of neutrons.
8. 1 amu is defined as \( \frac{1}{12} \) the mass of a carbon - 12 atom, not carbon - 14.
9. The nucleus contains protons (positive charge) and neutrons (no charge), so it has a net positive charge.
10. Carbon has an atomic number of 6. Carbon - 14 has 6 protons (atomic number = number of protons for an element).

Answer:

1. False. The difference between carbon - 12 and carbon - 13 is the number of neutrons.
2. True.
3. False. An atom is electrically neutral if it has the same number of protons and electrons.
4. False. Most of the mass of an atom resides in the nucleus and most of the volume of an atom resides in the electron cloud.
5. False. Electrons are the smallest and lightest subatomic particle.
6. False. Protons are much heavier than electrons.
7. False. Isotopes have different mass numbers.
8. False. \(1\ amu=\frac{1}{12}\) the mass of a carbon - 12 atom.
9. True.
10. False. Carbon - 14 has an atomic number of 6 and has 6 protons.