Evidence of a chemical change does NOT include A) producing a gas. B) change in color. C) change in shape. D) change in temperature.

The number of moles of c atoms in 3.20 moles of c2h60

In general, the rate of a reaction can be increased by 1. All of these 2. increasing the concentration of reactants. 3. increasing the temperature. 4. adding an appropriate catalyst.

When the concentrations of reactant molecules are increased, the rate of reaction increases. The best explanation for this phenomenon is that as the reactant concentration increases, A) the average kinetic energy of molecules increases.

At 50.14k a substance has a vapor pressure of 258.9 torr. calculate its heat of vaporization in kj/mol if it has a vapor pressure of 277.5 torr at 161.2k

Which three quantum numbers are associated with the 4d orbital?

How many protons are in chromium-58?

Which statement about the effusion rates of nitrogen and oxygen is true? Oxygen effuses 1.07 times faster than nitrogen. Nitrogen effuses 1.07 times faster than oxygen. Oxygen effuses 0.9 times faster than nitrogen. Nitrogen effuses 0.

Which of the following statements is true? A) Entropy is not a state function. B) Endothermic processes decrease the entropy of the surroundings, at constant T and P. C) Endothermic processes are never spontaneous.

Which of the following describes a chemical reaction? A. Molecules mix without interacting. B. Atoms in substances react with each other. C. Substances change shape but not properties. D. Molecules interact without bonds breaking.

How do we know stars are element factories?