How many grams of a stock solution that is 87.5 percent h2so4 by mass would be needed to make 275 grams of a 55.0 percent by mass solution? show all of the work needed to solve this problem.

What is the percent by mass of oxygen in fe2o3

What are several ways to reduce the effect of friction

An unknown substance is a white solid at room temperature and has a melting point of 78 °c. which of the following substances is most likely to be the identity of the unknown sample? a. naphthalene, a molecular solid with the formula c10h8 b. silica, a network solid held together by covalent bonds with the formula sio2 c. calcium chloride, an ionic compound with the formula cacl2 d. water, an molecular compound with the formula h2o