A system performed 145 kJ of work on the surroundings and absorbed 105 kJ of heat from the surroundings. What is the change in energy of the system?

Can someone check my work 98 5.05 acids and bases for this assignment you will be comparing acids and bases. the chart below will you organize the information needed: acids bases chemical properties (2) deodorant detergent vinger dish soap physical properties (2) orange juice toilet cleaner drain cleaner window cleaner ph level acid ph goes from 0-4 bases ph goes from 10-14 examples around you (2) vinger coffee lemon juice dark chocolate

How many moles of potassium hydroxide are needed to completely react with 2.94 moles of aluminum sulfate according to the following equation:

How many significant figures are in the following numbers ? a. 0.0002030 b. 2.000 c. 2.008900 d. 145.00