After three half-lives of an isotope 1 billion of those isotopes remain undecayed. How many atoms were in the original sample?

List the two type of transporst that the cell in orde to transport molecules acroos the membrane

This question is about electrolysis. metal spoons can be coated with silver. this is called electroplating. suggest one reason why spoons are electroplated?

An atom's configuration based on its number of electrons ends at 3p4. another atom has seven more electrons. starting at 3p, what is the remaining configuration? 3p63d34s2 3p43d54s2 3p64s23d3 3p44s23d