If only an element’s atomic number and weight are provided, what other atomic information can be determined for a neutral atom?
1. only the number of protons and electrons
2. the number of protons, electrons and neutrons
3. only the valence electrons
4. only the number of protons and neutrons
The correct answer is 2. The atomic number tells us the number of protons in the nucleus of an atom, and the atomic weight is approximately equal to the sum of the protons and neutrons in the nucleus. Therefore, by knowing the atomic number and weight, we can determine the number of protons, electrons, and neutrons in a neutral atom.
The correct answer is 2. The atomic number gives the number of protons in the nucleus of an atom, and the atomic weight gives the average mass of the atom, which is approximately equal to the number of protons plus neutrons. Therefore, with the atomic number and atomic weight, you can determine the number of protons, electrons, and neutrons in a neutral atom.
To determine what other atomic information can be determined for a neutral atom based on its atomic number and weight, let's understand the significance of these two quantities.
The atomic number represents the number of protons in the nucleus of an atom. It uniquely identifies the element and determines its position in the periodic table. For a neutral atom, the number of protons is equal to the number of electrons.
The atomic weight (also known as atomic mass) represents the average mass of all the isotopes of an element, taking into account their abundance. It is measured in atomic mass units (amu) and includes the combined mass of protons and neutrons in the nucleus.
Given this knowledge, we can answer the question:
Option 2: The number of protons, electrons, and neutrons can be determined.
To find the number of protons and electrons, you need to look at the atomic number. For a neutral atom, the number of protons is equal to the number of electrons.
To find the number of neutrons, you can subtract the atomic number from the atomic weight. Since the atomic weight includes both protons and neutrons, subtracting the atomic number (which represents the protons) gives you the number of neutrons.
Therefore, by knowing the atomic number and weight, you can determine the number of protons, electrons, and neutrons for a neutral atom (Option 2).