Answer:
a) heat it from 23.0 to 78.3
q = (50.0 g) (55.3 °C) (2.46 J/g·°C) =
b) boil it at 78.3
(39.3 kJ/mol) (50.0 g / 46.0684 g/mol) =
c) sum up the answers from the two calculations above. Be sure to change the J from the first calc into kJ
Explanation:
Answer: formic acid (HCOOH) contains the greatest mass of oxygen
Explanation:Please see attachment for explanation
Answer:
3:1
Explanation:
Lithium is a group 1 element. This means it would donate one electron to form the cation.
Nitrogen on the other hand is a group 5 element. It would accept 3 electrons to form the anion.
This means there has to be three lithium atoms, each donating an electron each to the nitrogen atom for a compound to be formed.
The formular for the ionic compound would be given as;
Li₃N
Hence the ration is 3:1
The word atom<span> is derived from the Greek </span><span> 'atomos' - </span><span>“indivisible.”
But the word 'atom' itself just means the smallest particle, not necessarily invisible.
</span><span>
</span>
Answer:
pH = 2.97
Explanation:
Aspirin, (HC₉H₇O₄), is in equilibrium with water, thus:
HC₉H₇O₄(aq) + H₂O(l) ⇄ C₉H₇O₄⁻(aq) + H₃O⁺(aq)
Ka = 3.0x10⁻⁴ = [C₉H₇O₄⁻][H₃O⁺] / [HC₉H₇O₄]
When you add 0.0050M of aspirine, the solution reach equilibrium when concentrations are:
[HC₉H₇O₄] = 0.0050M - x
[C₉H₇O₄⁻] = x
[H₃O⁺] = x
Replacing in Ka formula:
3.0x10⁻⁴ = [x][x] / [0.0050-x]
1.5x10⁻⁶ - 3.0x10⁻⁴X = X²
X² + 3.0x10⁻⁴X - 1.5x10⁻⁶ = 0
Solving for x:
x = - 0.00138 → False answer. There is no negative concentrations
x = 0.00108 → Right answer
As [H₃O⁺] = x; [H₃O⁺] = 0.00108M.
pH = -log[H₃O⁺]
<em>pH = 2.97</em>
