Assertion: chemical composition | /r/HasProperty | approximately 50% carbon
Facets:
value: by weight
type: OTHER
Source sentences:
text: The chemical composition of wood varies from species to species, but is approximately 50% carbon, 42% oxygen, 6% hydrogen, 1% nitrogen, and 1% other elements (mainly calcium, potassium, sodium, magnesium, iron, and manganese) by weight.