What do I search if my essay is based on the 6th mass extinction?

10-14. (a) when 100.0 ml of weak acid ha were titrated with 0.093 81 m naoh, 27.63 ml were required to reach the equivalence point. find the molarity of ha. (b) what is the formal concentration of a- at the equivalence point? (c) the ph at the equivalence point was 10.99. find pk. for ha. (d) what was the ph when only 19.47 ml of naoh had been added?

Acontainer holds 35.8 moles of gas under 10.0 atm of pressure at 70.0 c. what is the volume of the container?

How many moles of lead are in 1.50 x 10^12 atoms of lead? could you explain the answer as well and not just give it to me i am refreshing for finals and i need to know how to do it