What percentage of a substance remains after 7 half-lives have passed? A. 0.39
B. 2.5
C. 1.25
D. 0.78

If the density of water is 1.0 g/cm3, which of these materials would float in water, based on their densities? check all that apply. aluminum cork iron lead wax

If two atoms are bonded to a central atom with no lone pairs,how will they be arranged

In chemistry, the type of an atom (what element it is) is determined by: a) the number of protons it contains in its nucleus.b) the number of neutrons it contains in its nucleus.c) the number of protons it has in a cloud around the nucleus.d) the number of neutrons it has in a cloud around the nucleus.e) the number of electrons it exchanges with its neighbors.