What was johann dobereiners contribution to the development of the periodic table

If an element, X, can form an oxide that has theformula X2O3, then element X would most likely be located on the Periodic Table in the same group as (1) Ba (3) In (2) Cd (4) Na

Name the complex ion [cu (cn) 6]4-. the oxidation number of copper is + 2. enter the name.

5. Express the composition of each atom in shorthand form. a. zinc-64 b. chlorine-37 c. hydrogen-3 d. calcium-40

Gaseous ethane (CH3CH3) reacts with gaseous oxygen gas (O2) to produce gaseous carbon dioxide (CO2) and gaseous water (H2O). If 2.71 g of carbon dioxide is produced from the reaction of 3.31 g of ethane and 23.

James developed a plan to find the percent composition of the compound KClO3. His first step was to find the mass of the individual elements.

The density of an aqueous solution of nitric acid is 1.36 g/ml and the concentration is 2.48 m. what is the concentration of this solution in percent by mass?

In a crystal lattice of an ionic compound, A. Kind of a given charge are clustered together B. Ions are surrounded by ions of the opposite charge C. A sea of electrons surrounds the ions D. Neutral molecules are present

Discuss why two objects of made of the same type of matter at the same starting temperature with different masses increase in temperature at different rates when the same amount of thermal energy is transferred to each object.

An isotope contains 56 protons, 54 electrons, and 74 neutrons. What is the identity of the isotope?

How many ozone particles are needed to form 24 particles of oxygen gas?