Which of the following materials is most effective for stopping gamma radiation? explain your answer single sheet of paper one cm of water several cm of lead single sheet of aluminum foil

Write the empirical chemical formula of calcium with a mass percent of 38.8, phosphorus with a mass percent of 20.0, and oxygen with a mass percent of 41.3.

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.

The sum of the oxidation numbers in a neutral compound is always