Answer:
Anything not on the periodic table is an element non example! ... So, for a substance to be an element, all of its atoms must have the same number of protons. Examples of elements include hydrogen, lithium, nickel, and radium.
Explanation:
Answer:

Explanation:
You calculate the energy required to break all the bonds in the reactants.
Then you subtract the energy needed to break all the bonds in the products.
CH₃CH₂OH + 3O₂ ⟶ 2CO₂ + 3H₂O
Bonds: 5C-H 1C-C 1C-O 1O-H 3O=O 4C=O 6O-H
D/kJ·mol⁻¹: 413 347 358 467 495 799 467

Al, since it is the only metal in that list
When sodium hydroxide (NaOH) is added to benzoic acid (C
), sodium benzoate and water (
) are formed because benzoic acid is weak acid and NaOH is strong base. The reaction is shown in diagram 1. To the tube of sodium benzoate, if 6 m HCl is added, sodium benzoate salt will react with HCl and produce benzoic acid and sodium chloride, NaCl. The reaction is shown in diagram 2.