When oxygen combines with hydrogen, which substance is formed? 20.
A.
water
B.
vinegar
C.
hydrochloric acid
D.
hydrogen dioxide

A

Explanation:

hydrogen peroxide

When molecular hydrogen (H2) and oxygen (O2) are combined and allowed to react together, energy is released and the molecules of hydrogen and oxygen can combine to form either water or hydrogen peroxide. These two processes are represented by the two chemical equations shown at right.

Hydrogen peroxide (H2O2), a compound made up of two hydrogen atoms and two oxygen atoms, begins to breaks apart as soon as it contacts blood, creating that stinging sizzle.

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

practical process described pest part of scientific investigation.

because practical knowledge is powerful then therotical knowledge.