1) Which element has this 1s²,2s², 2p⁶, 3s², 3p⁶,4s², 3d¹⁰, 4p⁶, 5s²,4d¹⁰, 5p⁶, 6s², 4f¹⁴,5d¹⁰, 6p² configuration?

2) How many valence electrons in a species with one Cl, two O,and one unit negative charge a. 16 b. 18 c. 20 d. 22

3)Water has the formula H2O. Water can be made from the reactionof hydrogen and oxygen. If 2.0 g of hydrogen react fully with 2.0 gof oxygen, then ____ of water is made. a. 2.0 g b. 3.0 g c. 4.0 gd. 6.0 g

4)A skunk’s spray contains the foul-smelling compoundbutanethiol, C4H8S. What is the percent by mass of sulfur in thiscompound (to the nearest whole percent)