Answer is: the hydronium ion concentratio is 1.71×10⁻⁷ mol/dm³ and pH<6.76.
The Kw (the ionization constant of water) at 40°C is 2.94×10⁻¹⁴ mol²/dm⁶ or 2.94×10⁻¹⁴ M².
Kw = [H₃O⁺] · [OH⁻].
[H₃O⁺] = [OH⁻] = x.
Kw = x².
x = √Kw.
x = √2.94×10⁻¹⁴ M².
x = [H₃O⁺] = 1.71×10⁻⁷ M; concentration of hydronium ion.
pH = -log[H₃O⁺].
pH = -log(1.71×10⁻⁷ M).
pH = 6.76.
pH (potential of hydrogen) is a numeric scale used to specify the acidity or basicity an aqueous solution.
Answer:
The first one.
Explanation:
When comparing two fractions with variables like this, it's important to get to the same denominator in order to compare apples with apples and then be able to do not only comparisons but also perform additions/subtractions.
Question is which denominator to use and how to reach it.
In this case, the question and the answer choices do the work for you. The question asks which one is the LEAST common denominator, and the answers show denominators x² and 4x². The smallest of these is x², however, we can't simplify the first fraction to get to the x² denominator, so we'll go for the 4x².
So, the first fraction has already the correct denominator (4x²), we just have to transform the second one.
We multiply it by 1, expressed in a different way. Since we're multiplying by one, we're not affecting the value, just the way it looks.
Let's do it!, to get the denominator to go from x² to 4x², we need to multiply it by 4... so we'll multiply by 4/4 (which is 1, neutral for the multiplication).
And now you have both fractions on the same denominator, without having changed their value, just their looks
Answer:
Lattice energy is <em>the energy required to convert a mole of ionic solid into its constituent ions in the gas phase</em>
Explanation:
Lattice energy is usually calculated by the Born-Haber cycle, from the affinity energies and sublimation ethalphy values. It is used as an estimation of the ionic energy strength between the ions in an ionic compound.
It is defined as the energy needed to broke 1 mol of a given ionic compound into its ions in the gaseous state. For example, the lattice energy for sodium chloride (NaCl) is the energy required to separate 1 mol of solid ionic compound (NaCl(s)) and produce the sodium and chlorine ions in the gas phase: Na⁺(g) and Cl⁻(g).
Answer:
Appearance. Pure rock salt is colorless. However, when found underground it is generally not completely pure, so may have yellow, red, gray or brown hues. It is either transparent or translucent and when you shine a light on it, its luster is vitreous, meaning it appears shiny and glassy.
Explanation:
Answer: Edge length of the unit cell = 628pm
Explanation: For a body centred cubic structured system, the relationship between the edge length of the unit cell and radius of the atoms in the structure is
Edge length of Unit cell (a) = (4R)/(√3)
R = 272pm = (272 × (10^-12))m = (2.72 × (10^-10))m
a = (4 × (2.72 × (10^-10)))/(√3)
a = (6.28157 × (10^-10))m = 628pm
