Which occurs more often on earth? Physical or Chemical changes?

In the equation 2 H2 + O2 - > 2H2O, H2, O2, and H2O are all trace elements. Only H2O is a compound. Only H2 and O2 are compounds. H2, O2, and H2O are ALL elements. H2, O2, and H2O are ALL compounds.

Why can't we carry an umbrella during lighting?

Is oxygen gas (O2) a compound or an element? Is hydrogen gas (H2) a compound or an element?

What are the raw materials of respiration

A graduated cylinder contains 22.0 mL of water. What is the new water level after 34.0g of silver metal with a density of 10.5 g/mL is submerged in the water?

What is the pH of pure water

What is the molar mass, in grams, of a mole of an element equal to? O A. the number of electrons in the element O B. the atomic weight of the element OC. the atomic number of the element OD. the number of neutrons in the element

What substance is not a compound

Consider the following exothermic reaction and predict how the change below will affect the concentration (increase, decrease, stay the same) of each component in the system as the equilibrium is reestablished.

How does the electron structure of atoms change when they form chemical bonds