Does anyone know good chemistry apps/websites for college that are free?

The following reaction shows the products when sulfuric acid and aluminum hydroxide react. al(oh)3 + h2so4 → al2(so4)3 + h2o the table shows the calculated amounts of reactants and products when the reaction was conducted in a laboratory. sulfuric acid aluminum hydroxide initial amount of reactant 40 g 15 g theoretical yield of water from reactant 14.69 g 10.38 g what is the approximate amount of the leftover reactant? 11.73 g of sulfuric acid 10.33 g of sulfuric acid 11.12 g of aluminum hydroxide 13.67 g of aluminum hydroxide

How hot is the suns corona? (integrated science)

Astudent uses universal ph paper to find the ph of three solutions . solution a has a ph of 5 solution b has a ph of 11 and solution c has a ph of 7 identify which solution is acidic which solution is neutral and which solution is basic