What is the ionisation energy of an atom

Several mountains together form a mountain . a few of these combined form a mountain system. several systems combined form a mountain , which can stretch thousands of miles in length.

True or false when elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it.

What is the weight of a 8-kg substance in n, kn, kg·m/s2, kgf, lbm·ft/s2, and lbf?