1. The heating system that uses the energy

of the sun to produce heat is a

A. calculate the mass percent of NaHCO3 based on the manufacturer's list of ingredients: 325mg aspirin, 1000 mg citric acid, 1916 mg NaHc03.

Which of the following reactions are redox reactions? a. H2CO3 (aq) + 2NH3 (aq) → 2NH4 + (aq) + CO32 - (aq) b. 2Mg (s) + O2 (g) + 2H2O (l) → 2Mg2 + (aq) + 4OH - (aq) c. Zn (NO3) 2 (aq) + 2NaOH (aq) → Zn (OH) 2 (s) + 2NaNO3 (aq) d.

At the top of the candle solid wax changes into liquid wax what is the name of the process

Which of the following is a product formed when BaO and H2O react together? BaO H2 O2 Ba (OH) 2

Atoms of what two types of elements would form an ionic bond? a. two metals b. two nonmetals c. a metal and a nonmetal d. two metals and two nonmetals

If entropy increases and enthalpy and temperature remain constant, the Gibbs free energy Group of answer choices A. decreases B. increases C. entropy has no effect

The number 0.000402 expressed in exponential notation is

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.

Bromine (Br,) is observed as a red-brown color During the bromination of benzene, an electrophilic aromatic substitution, why does the red-brown color of Br2 disappear as the reaction progresses? a.

Why is steel going through a fluid phase during its production