What is an acid? select all that apply.
a substance that releases hydroxide ions in water
a substance that releases hydrogen ions in water
a substance that tastes sour
a substance with a ph below 7
a substance that tastes bitter

A substance that releases hydrogen ions in water.; A substance that tastes sour.; A substance with a pH below 7.

Explanation:

An acid reacts with water releasing Hydrogen ions, this leads to a decrease in pH, below neutral or 7. The Hydrogen ions also give a sour taste.

A substance that releases hydrogen ions in water.; A substance that tastes sour.; A substance with a pH below 7.

Explanation:

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.

all matter is made up of atoms

in any element all atoms are the same

elements in a compound are always in a constant ratio: apex