A neutral atom possesses an atomic number of 13 and an atomic mass of 27. Three electrons are lost.
From what region of the atom are they lost?
Responses
both inside and outside the nucleus
both inside and outside the nucleus
outside the atom
outside the atom
inside the nucleus
inside the nucleus
outside the nucleus
7 answers
Three electrons are lost, so they are lost from outside the nucleus. Therefore, the correct response is "outside the atom".
What does an atomic number represent in an atom?
Responses
number of protons
number of protons
number of electrons
number of electrons
number of neutrons
number of neutrons
number of protons and neutrons
Responses
number of protons
number of protons
number of electrons
number of electrons
number of neutrons
number of neutrons
number of protons and neutrons
The atomic number represents the number of protons in an atom. Therefore, the correct response is "number of protons".
What differs between a radioactive isotope and a stable isotope of the same element?
Responses
Stable isotopes are usually heavier.
Stable isotopes are usually heavier.,
Stable isotopes break down quickly.
Stable isotopes break down quickly.,
Radioactive isotopes do not break down.
Radioactive isotopes do not break down.,
Radioactive isotopes last for less time.
Responses
Stable isotopes are usually heavier.
Stable isotopes are usually heavier.,
Stable isotopes break down quickly.
Stable isotopes break down quickly.,
Radioactive isotopes do not break down.
Radioactive isotopes do not break down.,
Radioactive isotopes last for less time.
The correct response is "Radioactive isotopes break down", as they undergo radioactive decay and emit radiation over time. Stable isotopes, on the other hand, do not break down or undergo radioactive decay. The response "Stable isotopes are usually heavier" is not accurate as the weight of isotopes can vary, regardless of their stability or radioactivity.
How do the atomic mass and atomic number compare for helium?
Responses
The atomic number is greater.
The atomic number is greater.
Helium does not have an atomic number.
Helium does not have an atomic number.
The atomic mass and atomic number are equal.
The atomic mass and atomic number are equal.
The atomic mass is greater.
Responses
The atomic number is greater.
The atomic number is greater.
Helium does not have an atomic number.
Helium does not have an atomic number.
The atomic mass and atomic number are equal.
The atomic mass and atomic number are equal.
The atomic mass is greater.
The correct response is "The atomic mass and atomic number are equal" for helium. Helium has an atomic number of 2, which represents the number of protons in its nucleus. Its atomic mass is also approximately 4 atomic mass units (amu), which takes into account the combined mass of protons and neutrons in the nucleus. Therefore, they are equal for helium.