How many grams of oxygen (O2) is required to burn 28.8 g of ammonia (NH3)? 4NH3 + 7O2 → 4NO2 + 6H2O

Molar Masses

NH3=17.0305 g/mol

O2=31.998 g/mol

NO2=46.0055 g/mol

H2O=18.0153 g/mol

a)15.3 g
b)94.9 g
c)54.1 g
d)108 g

The molecular formula for caffeine is cshion402. which of the following elements is not found in caffeine?

Adrop of acetone (nail polish remover) has a mass of 35 mg and a density of 0.788 g/cm3. what is its volume in cubic centimeters?

Pegmatites are igneous rocks in which the individual minerals are very large. typically, the minerals are all light-colored quartz, feldspar and muscovite. if you were given a black and white photograph of a pegmatite in a quarry (where the rock has been blasted and broken), what physical properties could you use to identify those three minerals in this hypothetical photo? describe each mineral and the specific diagnostic properties. be specific.