If water is cooled from 90°C to 40°C will the energy lost be a positive number or a negative number? Why?

What is the mass defect of a mole of nuclei with 1.8 x 10^15 j/mol binding energy?

An atom of sodium-23 (atomic number = 11) has a positive charge of +1. give this information, how many electrons does it have? how many proteins and neutrons does this atom have

An excess of lithium oxide undergoes a synthesis reaction with water to produce lithium hydroxide li2o+h2o→2lioh if 1.05 g of water reacted, what is the theoretical yield of lithium hydroxide? a) 5.83 x 10–2 g lioh b) 1.17 x 10–1 g lioh c) 2.79 x 100 g lioh d) 1.40 x 100 g lioh