What is the SI unit that refers to the amount of a substance?

Between 2014 and 2016, more than 25,000 children in flint, michigan, drank water that was contaminated with lead from lead pipes. during this time, the city claimed the water was safe to drink. which of these actions could the city have taken to ensure that the drinking water was free from lead?

If you chip a tooth, most likely you will go to the dentist to have the missing material filled in. currently the material used to fill in teeth is a polymer that is flexible when put in, yet is hardened to the strength of a tooth after irradiation with blue light at a wavelength of 461 nm. what is the energy in joules for a photon of light at this wavelength?

Predict the products of the following acid-base reactions, and predict whether the equilibrium lies to the left or to the right of the reaction arrow.part ao2-(aq)+h2o(l)< => express your answer as part of a chemical equation. identify all of the phases in your answer.o2-(aq)+h2o(l) < => oh-(aq)+oh-(aq)part bpredict whether the equilibrium lies to the left or to the right of the equation in previous part.h2o is a stronger acid than oh–, so the equilibrium lies to the right.h2o is a weaker acid than oh–, so the equilibrium lies to the left.h2o is a stronger acid than oh–, so the equilibrium lies to the left.h2o is a weaker acid than oh–, so the equilibrium lies to the right.part cch3cooh(aq)+hs? (aq) < => express your answer as part of a chemical equation. identify all of the phases in your answer.ch3cooh(aq)+hs-(aq) < => h2s(aq)+c2h3o2-(aq)h2s(aq)+c2h3o2-(aq)part dpredict whether the equilibrium lies to the left or to the right of the equation in previous part.ch3cooh is a weaker acid than h2s, so the equilibrium lies to the right.ch3cooh is a weaker acid than h2s, so the equilibrium lies to the left.ch3cooh is a stronger acid than h2s, so the equilibrium lies to the right.ch3cooh is a stronger acid than h2s, so the equilibrium lies to the left.part eno2-(aq)+h2o(l) < => express your answer as part of a chemical equation. identify all of the phases in your answer.no2-(aq)+h2o(l) < => part fpredict whether the equilibrium lies to the left or to the right of the equation in previous part.hno2 is a stronger acid than h2o, so the equilibrium lies to the right.hno2 is a weaker acid than h2o, so the equilibrium lies to the left.hno2 is a stronger acid than h2o, so the equilibrium lies to the left.hno2 is a weaker acid than h2o, so the equilibrium lies to the right.