Must new substances be formed when you observe a chemical property? explain

A sample containing only carbon, calcium, and nitrogen is analyzed in a combustion train, producing solely carbon dioxide, calcium oxide, and nitrogen dioxide. The reaction of a 426.74 mg sample of the unknown produces 298.

Severe acid rain caused by factory emissions can erode the leaves of plants. Which statement best explains why this would harm the plant life?

What is the mass number of beryllium with 5 neutrons

7.25 in scientific notation

Energy states of atoms containing more than one electron are influenced by nucleus-electron and electron-electron interactions. Which of the following statements correctly describes these effects? A.

Alcl3) and lithium sulfate (li2so4) (note - this is a double replacement reaction. you need this information to predict the products of the reaction)

Which type of bond is present in hydrogen sulfide (H2S) ? The table of electronegativities is given.

What is the oxidation state of S in HSO4^2-?

Which of the following mountain ranges is the result of a continent-continent orogeny? A) Andes Mountains B) Hawaiian Islands C) Appalachian Mountains

Why do atoms share electrons in covalent bonds?