1) which of the following is the smallest unit of a chemio
tallest unit of a chemical element?

Nanomachines will work with atoms, not nuclei. The smallest unit of a chemical element, about a third of a nanometer in diameter. Atoms make up molecules and solid objects.

Explanation:

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.