Question

select all the correct answers. why do the atoms in a piece of copper metal have no net charge? the charges of the positive and negative copper ions cancel each other out. the number of electrons surrounding each copper nucleus doesnt change. copper atoms cant lose electrons without a substance present to gain electrons. when a copper atom loses electrons, it also loses a corresponding number of protons. the copper atoms exchange neutrons instead of electrons.

Explanation:

1. Analyze Option 1: Copper metal consists of neutral atoms (not ions in the context of net charge of atoms in metal; metal atoms in bulk metal are neutral, and ions would be in compounds). So this is incorrect.
2. Analyze Option 2: In a copper atom, the number of electrons (negative charge) is equal to the number of protons (positive charge) in a neutral atom. The number of electrons around each copper nucleus (in neutral state) doesn't change in the metal (no net gain or loss of electrons), so the positive (protons) and negative (electrons) charges balance, resulting in no net charge. This is correct.
3. Analyze Option 3: The net charge of an atom in copper metal is not related to the need for another substance to gain electrons. Atoms in metal are neutral due to electron - proton balance, not because of electron transfer requirements to other substances. This is incorrect.
4. Analyze Option 4: Protons are in the nucleus and do not change when an atom loses electrons (electron loss is a chemical process, proton number is a characteristic of the element). So this is incorrect.
5. Analyze Option 5: Neutrons are neutral and do not participate in charge balance, and copper atoms do not exchange neutrons to achieve charge balance (charge balance is between protons and electrons). This is incorrect.

Answer:

B. The number of electrons surrounding each copper nucleus doesn't change.