Answer:
A chemical formula for a molecular compound represents the composition of <u><em>a molecule.</em></u>
Explanation:
Chemical formulas are alphanumeric expressions that are used to indicate the composition of chemical substances. They consist of chemical symbols that indicate the elements that form a compound; The number of atoms provided by each element is also indicated by the use of a subscript, that is, a small number that is placed below and to the right of each element that so requires. When an element does not have a subscript, it is understood that there is only one atom of it in the substance.
Each molecule corresponds to a chemical formula, as well as a name according to the rules of the chemical nomenclature.
Then, <u><em>a chemical formula for a molecular compound represents the composition of a molecule.</em></u>
Answer:
pKa = 3.675
Explanation:
∴ <em>C</em> X-281 = 0.079 M
∴ pH = 2.40
let X-281 a weak acid ( HA ):
∴ HA ↔ H+ + A-
⇒ Ka = [H+] * [A-] / [HA]
mass balance:
⇒<em> C</em> HA = 0.079 M = [HA] + [A-]
⇒ [HA] = 0.079 - [A-]
charge balance:
⇒ [H+] = [A-] + [OH-]... [OH-] is negligible; it comes from to water
⇒ [H+] = [A-]
∴ pH = - log [H+] = 2.40
⇒ [H+] = 3.981 E-3 M
replacing in Ka:
⇒ Ka = [H+]² / ( 0.079 - [H+] )
⇒ Ka = ( 3.981 E-3 )² / ( 0.079 - 3.981 E-3 )
⇒ Ka = 2.113 E-4
⇒ pKa = - Log ( 2.113 E-4 )
⇒ pKa = 3.675
Answer:
P₂ = 28.5 torr
Explanation:
Given data:
Initial pressure = 38 torr
Initial volume = 500 L
Final volume = 677 L
Final pressure = ?
Solution:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = Initial volume
P₂ = Final pressure
V₂ = Final volume
Now we will put the vales in formula.
P₁V₁ = P₂V₂
P₂ = P₁V₁ /V₂
P₂ = 38 torr × 500 L / 667 L
P₂ = 19000 torr. L / 667 L
P₂ = 28.5 torr
Well definitely a scientist
