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:
18.5 years
Explanation:
(6 x 10^23)/(10^15 x 1.03 x 3600 x 24 x 365)
Hope this helps!
By using the formula, mass = density x volume, we
calculate mass in grams
20.0 mL CH₃COOH x (1.05 g / mL) = 21.0
g CH₃COOH
To find the moles, molar mass of CH₃COOH = 60.05g/mol<span>
21.0 g </span>CH₃COOH x (1 mole CH₃COOH / 60.05 g CH₃COOH)
= 0.350 moles CH₃COOH
To find molarity,<span>
[</span>CH₃COOH] = moles CH₃COOH / L of solution = 0.350 /
1.40 = 0.250 M CH₃COOH<span>
When </span>CH₃COOH is dissolved in water, it produces
small and equal amounts of H₃O⁺+ and C₂H₃O₂⁻.
<span>
Molarity , </span>CH₃COOH<span> + H</span>₂O <==> H₃O⁺ + C₂H₃O₂⁻
<span>
<span>Initial 0.250 0 0 </span>
Change -x x x
Equilibrium 0.250-x x x
K</span>ₐ = [H₃O⁺][C₂H₃O₂⁻] / [HC₂H₃O₂] = (x)(x) /
(0.250-x) = 1.8 x 10⁻⁵
<span>Since K</span>ₐ is relatively small, we can neglect the -x
term after 0.250 to simplify
<span>x</span>² / 0.250 = 1.8 x 10⁻⁵
x² = 4.5 x 10⁻⁶
<span>
x = 2.1 x 10</span>⁻³<span> = [H</span>₃O⁺]
pH = -log [H₃O⁺] = -log (2.1 x 10⁻³) = 2.68
Ions are formed when atoms lose or gain electrons in order to fulfill the octet rule and have fuller valence electron shells.
