Answer: I disagree. Elements form all pure substances, but some pure substances include elements bonded together to form molecules and compounds.
Explanation:
Pure substances are those that have a uniform and constant (invariable) composition.
That condition is met by both elements and compounds.
Elements are pure substances of one only kind of atoms. For example, gold, oxygen, sodium, hydrogen, are pure substances that arer elements. There are 118 elements known and they are all listed in the periodic table.
Compounds are pure substances formed by two or more different kind of atoms. Water (H₂O), table salt (NaCl), and ethanol (CH₃-CH₂OH), are examples of pure substances that are compounds. There are pratically infinite different compounds.
In conclusion, compounds are also pure substances, since every sample of a given compound has always the same kind of elements bonded in the same way.
Is there supposed to be a practice?
<span>They have similar or common ancestor. The similarities inherited from the common ancestor as in the case of homologous organs. In evolutionary biology a group of organisms share a common descent if they have a common ancestor. There are many other examples like in the case of hemoglobin to prove the theory of common ancestor</span>
N=3^K-1 I really don't know how to explain it but that's the formula <span />
Answer: #20
Explanation:
if the sun got dimmer then plants would that need a high tempature would not be able to grow it would also be very cold
