What is the percent by mass of oxygen in ca(oh)2? [formula mass = 74.1]

3.) for each of the following compounds, draw the major organic product of reaction with hcl or naoh and circle whether the starting materials and products will be more soluble in organic solvent or water benzoic acid + hcl: benzoic acid + naoh: oh benzoic acid water/organic water organic fluorenone hс: fluorenone + naoh: fluorenone water/organic water/organic веnzocaine + hci: benzocaine + n»oh: h2n benzocaine water/organic water organic o=

Can someone me with 1 to 4 plz. fast

At 300 mm hg, a gas has a volume of 380 l, what is the volume at standard pressure