What is the key characteristic of an oxidation–reduction reaction?
A.
Electricity is gained.
B.
Electricity is lost.
C.
Electrons are exchanged.
D.
Electrons are gained.
E.
Electrons are lost.

Which is true of the reactants in this displacement reaction? fe + 2hcl fecl2 + h2 a. the reactants are located to the left of the arrow in the chemical equation. b. the reactants contain 1 iron atom, 2 hydrogen atoms, and 1 chlorine atom. c. the reactants are the atoms, molecules, or compounds formed in the reaction. d. the reactants have the same physical and chemical properties as the products.

Hot air balloons float in the air because of the difference in density between cold and hot air. in this problem, you will estimate the minimum temperature the gas inside the balloon needs to be, for it to take off. to do this, use the following variables and make these assumptions: the combined weight of the pilot basket together with that of the balloon fabric and other equipment is w. the volume of the hot air inside the balloon when it is inflated is v. the absolute temperature of the hot air at the bottom of the balloon is th (where th> tc). the absolute temperature of the cold air outside the balloon is tc and its density is ďc. the balloon is open at the bottom, so that the pressure inside and outside the balloon is the same. as always, treat air as an ideal gas. use g for the magnitude of the acceleration due to gravity.

Given sno2 + 2h2 - sn + 2h20 tin oxide reacts with hydrogen to produce tin and water. how many moles of sno2 are needed to produce 500.0 grams of sn?