D, 2Cu + O2 → 2CuO. A is wrong because oxygen is a diatomic element, meaning it always has to come in the form of O2 in the case of gas. B is wrong because the equation isn't balanced correctly; there's two oxygens on the reactants side, while only one oxygen on the products side. C is wrong because it's saying you're STARTING OUT with CuO already: that doesn't correspond with the word problem. Thus leaves D, where the equation is balanced correctly, has the diatomic oxygen, and ends with CuO.
Answer:
Molality, Solvent, Solute, Mole fraction, Molarity.
Explanation:
The expression of concentration that provides the moles of solute per kilograms of solvent is Molality. This in the only expression referred to the solvent.
A solution is made up of 0.15 grams of sodium chloride in 1 liter of water. For this solution, the Solvent is water. When water is present, it is usually considered the solvent.
A solution is made up of 0.15 grams of sodium chloride in 1 liter of water. For this solution, the Solute is sodium chloride. There can be 1 or more solutes in a solution.
If you place 5 moles of sodium chloride and 4 moles of sucrose into 11 moles of water, the Mole fraction of sodium chloride would be 0.25. The mole fraction is equal to the moles of a substance divided by the total number of moles.
A way to express concentration that provides the moles of solute per liter of solution is Molarity.
J.j. Thomson discovered them
How many valence electrons are in an atom of phosphorus?
a. 2
c. 4
b. 3
d. 5 Please select the best answer from the choices provided A B C D
There are five valence
electrons are in an atom of phosphorus. The answer is letter D.