An iron ore sample contains plus other impurities. A 729-g sample of impure iron ore is heated with excess carbon, producing 277 g of pure iron by the following reaction: What is the mass percent of in the impure iron ore sample?

Of the following, which does not signify a chemical reaction? 1) tarnish 2) release of heat 3) changing state 4) release of gas

A scientist eliminated all living organisms in a jar of soup by heating it. He then left the soup jar uncovered for some days. After a few days, he saw molds in the soup. What most likely formed the mold?

To classify a substance as an Arrhenius acid or base, or as a Brønsted-Lowry acid or base, you must consider how the substance behaves when it dissolves in water. Ammonia forms an aqueous solution according to the following chemical equation.

Dead leaves decaying, is it a chemical or physical change

Is vinegar a compound or a mixture?

A change of temperature equal to one kelvin is equal to a change of temperature of how many degrees celsius?

A solution has [h3o+] = 4.2*10-5 m. use the ion product constant of water kw=[h3o+][oh-] to find the [oh-] of the solution.

A. A rapid cooking method that uses high heat from a source located above the food.

What is the number of copper atoms in 1naira coin which weighs 7.39g assuming the material of which the coil is made is 86% copper Na=n/n number of moles/n

Which of the following statements are consistent with Rutherford's nuclear theory as it was originally stated? (A) The volume of an atom is mostly empty space. (B) The nucleus of an atom is small compared to the size of the atom.