10 mL of a 1.0 solution is diluted to 100 mL. Then 10 mL of the diluted solution is removed and diluted again to 100 mL. What is the concentration of the second dilution?

Based on the position vs. time graph which velocity vs. time graph would correspond to the data

1)each group 16 element has how many valence electrons? ( )4 ( )6 ( )8 ( )16 2)how many dots appear in the dot structure for calcium ion, ca2+? ( )zero ( )one ( )two ( )eight 3) which of the following atoms forms a cation to obtain an octet of outer shell electrons? ( )magnesium ( )oxygen ( )fluorine ( )helium 4) an al3+ ion contains 13 protons and 10 electrons. ( )true ( )false 5) valence and non-valence electrons are represented in lewis dot structures. ( )true ( )false

Match the mixture with the substance// i really need on this guys (it’s a pic btw)