<span>John Dalton introduced a theory proposing that elements vary because of the mass of their atoms.
He said in his theory that all matter is made up of indivisible blocks called atoms. He also stipulated in his theory that elements are identical thus, have different sizes and masses.
Dalton's theory was different from Niels Bohr who proposed a new atomic model which was also commonly known as the modern atomic theory. Bohr's theory says that atoms are arranged in circular orbits around the nucleus. He patterned his model as the solar system.
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A lemon juice cleans a penny. I believe this to be the answer because the lemon cleans the penny but no molecules change
On the periodic table it is the number on the bottom of the element.
<span>If you know the amount of neutrons you can add it to the number of protons to find the atomic mass NUMBER, which is a good approximate of the atomic mass. </span>
Answer:
14.3mL you require to reach the half-equivalence point
Explanation:
A strong acid as HClO₄ reacts with a weak base as CH₃CH₂NH₂, thus:
CH₃CH₂NH₂ + HClO₄ → CH₃CH₂NH₃⁺ + ClO₄⁻
As the reaction is 1:1, to reach the equivalence point you require to add the moles of HClO₄ equal to moles CH₃CH₂NH₂ you add originally. Also, half-equivalence point requires to add half-moles of CH₃CH₂NH₂ you add originally.
Initial moles of CH₃CH₂NH₂ are:
20.8mL = 0.0208L × (0.51mol CH₃CH₂NH₂ / 1L) =
0.0106moles CH₃CH₂NH₂
To reach the half-equivalence point you require:
0.0106moles ÷ 2 = 0.005304 moles HClO₄
As concentration of HClO₄ is 0.37M, volume you require to add 0.005304moles is:
0.005304 moles HClO₄ ₓ (1L / 0.37mol) = 0.0143L =
<h3> 14.3mL you require to reach the half-equivalence point</h3>
