Answer:
Empirical formula is: C₂H₅
Explanation:
The chemical equation of burning of a compound that conatins only Carbon and Hydrogen is:
CₓHₙ + O₂ → XCO₂ + n/2H₂O
That means the moles of CO₂ produced are the moles of Carbon in the compound and moles of hydrogen are twice moles of water. Empirical formula is the simplest ratio between moles of each element in the compound. Thus, finding molse of C and moles of H we can find empirical formula:
<em>Moles C and H:</em>
Moles C = Moles CO₂:
7.851g CO₂ ₓ (1mol / 44g) = 0.1784 moles CO₂ = Moles C
<em />
Moles H = 2 Moles H₂O
4.018g H₂O ₓ (1mol / 18.01g) = 0.2231 * 2 = 0.4417 moles H
<em>Ratio C:H</em>
The ratio between moles of hydrogen and moles of Carbon are:
0.4417 moles H / 0.1784 moles C = 2.5
That means there are 2.5 moles of H per mole of Carbon. As empirical formula must be given only in whole numbers,
<h3>Empirical formula is: C₂H₅</h3>
Explanation:
The required concentration of M1 =0.222 M.
The required volume of is V1 =225 mL.
The standard solution of is M2 =16 M.
The volume of standard solution required can be calculated as shown below:
Since the number of moles of solute does not change on dilution.
The number of moles
Hence, 3.12 mL of 16 m nitric acid is required to prepare 0.222 M and 225 mL of nitric acid.
It’s option c. When resources are limited competition will increase => one will survive while other dies=> population will decline.
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BLACKSHARK
Answer:
Weak acid - strong base
Explanation:
H₃PO₄ → Phosphoric acid.
This is a weak that has three dissociations in order to give hydronium to the medium and to produce the phosphate anion. The equations are:
H₃PO₄ + H₂O ⇄ H₃O⁺ + H₂PO₄⁻ Ka1
H₂PO₄⁻ + H₂O ⇄ H₃O⁺ + HPO₄⁻² Ka2
HPO₄⁻² + H₂O ⇄ H₃O⁺ + PO₄⁻₃ Ka3
As the H₃PO₄ is a weak acid then the water behaves as a strong base.
If we follow the Brownsted Lory idea, water becomes a strong base cause it receives the H⁺ from water, then the H₃O⁺ becomes the conjugate weak acid.
Anions from the H₃PO₄, diacid phosphate and monoacid phosphate assume the rol of the conjugate strong base, they all recieve proton but this is a special case, because both anions can recieve all release the proton. That's why, they also are amphoteric