Hydrogen and what other substance is known to form water?Group of answer choicesoxygenheliumsiliconenirogen

Hydrogen combines with elements such as oxygen, sulfur, selenium, and telluride to form compounds, viz., H2O, H2S, H2Se, H2Te. Predict the compound that exists in either liquid state or gaseous state (at a normal temperature of 25 oC). Give a reason for the answers.

Which two substances are the main elements that make hard water?Group of answer choicesCalciumMagnesiumSodium

Hydrogen and Oxygen React to Form Water

Give the names of three atomic species of hydrogen.

State some sources of hydrogen.