How are we meant to know if a base is soluble or insoluble. Please help quick :-)

Why do scientists look for patterns in the world? a. patterns can explain observations. b. patterns never change, no matter what. c. patterns are easy for scientists to detect. d. patterns are all the same, through all time.

What is the result of multiplying (2.5 × 1010) × (2.0 × 10-7)? a. 5.0 × 103 b. 5.0 × 10-3 c. 5.0 × 1017 d. 5.0 × 10-17

An atom of lithium (li) and an atom of chlorine (cl) engage in a chemical reaction. which correctly describes the structure of the resulting chemical compound? hint: consider the class of each element. the chemical compound will have a network structure. the chemical compound will have triple bonds. the chemical compound will have a ball-and-stick structure. the chemical compound will have double bonds.