Early wheels were simple wooden disks with a hole for the axle. In the early Roman empire, most horse-carts used a design featuring two chords across the wheel. The spoked wheel was invented much more recently, and allowed the construction of lighter and swifter vehicles.
Chromium(III) sulfide. Chromium(III) Sulfide is the inorganic compound with the formula Cr2S3. It is a brown-black solid. Chromium sulfides are usually nonstoichiometric compounds, with formulas ranging from CrS to Cr0.67S (corresponding to Cr2S3). Preparation.
What is the ionic charge on the chromium ion in the ionic compound that has the formula Cr2O3? The compound is Chromium(III) Oxide. Chromium is 3+, since the compound has to have a charge equal to 0. Since there is 2 chromium atoms each chromium atom must have a charge â¦of 3+ to balance out the 3(2-) charges of each oxygen atom; 2x+3(-2)=0, transpose for x(chromium), (in case you need the working out).