What is the formula for the percent of an element in a compound

Determine the concentrations of na2co3, na, and co32 - in a solution prepared by dissolving 2.35 * 10-4 g na2co3 in 2.00 l of water. express all three concentrations in molarity.

Using an extinction coefficient of 15,000 M-1cm-1, calculate the concentration (in mM) of a molecule with an absorbance value of 0.200. You can assume the standard cuvette pathlength of 1 cm.

What can you predict about an element from its position in the periodic table?

What are the products of the ozonolysis of alkene

A sample of an element has a mass of 34.261 grams and a volume of 3.8 cubic centimeters. To which number of significant figures should the calculated density of the sample be expressed? (1) 5 (3) 3 (2) 2 (4) 4

If chlorine gas is bubbled through an aqueous solution of sodium iodide, the result is elemental iodine and aqueous sodium chloride solution. what kind of reaction took place?

In a solution such as salt water, the component that is dissolved is called the O solute O solvent O suspension O colloid

Which is the balanced chemical equation showing hydrogen peroxide (h2o2) decomposing into hydrogen (h2) and oxygen (o2) ? 1. h2 + o2 → h2o2 2. 2 h2o2 → 2 h2 + o2 3. h2o2 → h2 + o2 4. 2 h2 + o2 → 2 h2o2?

Assuming constant pressure, rank these reactions from most energy released by the system to most energy absorbed by the system, based on the following descriptions: A. Surroundings get colder and the system decreases in volume. B.

Zircon is a mineral with the empirical formula ZrSiO4. If all the zirconium is 90Zr, all the silicon is 28Si, and all the oxygen is 16O, what mass of oxygen is present in 10. g of zircon?