Take a sample of lead and oxygen. They contain different atoms and the density of solid lead is much greater than that of gaseosu oxygen. Decide whether the density of the nucleus in a lead atom is greater than, approximately equa to, or less than that in an oxygen atom.

Explanation

To determine whether the density of the nucleus in a lead atom is greater than, approximately equal to, or less than that in an oxygen atom, we can follow these steps:

### Step 1: Understand the Concept of Density
Density is defined as mass per unit volume. In the case of atomic nuclei, we consider the mass of protons and neutrons (nucleons) and the volume they occupy.

### Step 2: Recognize the Composition of Nuclei
Both lead (Pb) and oxygen (O) nuclei are made up of protons and neutrons. The number of protons and neutrons in lead is significantly higher than in oxygen. Lead has 82 protons and a varying number of neutrons (commonly 126), while oxygen has 8 protons and typically 8 neutrons.

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