<span>The best choice is hypochlorous acid nitrous acid (HNO2) because it has the nearest value of pK to the desired pH.
pKa of </span>nitrous acid<span> is 3.34
If we know pKa and pH values, we can calculate the required ratio of conjugate base (NO2⁻) to acid (HNO2) from the following equation:
pH=pKa + log(conc. of base)/( conc. of acid)
</span><span>3.19=3.34 + log c(NO2⁻)/c(HNO2)
</span><span>3.19 - 3.34 = log c(NO2⁻)/c(HNO2)
-0.15 = log c(NO2⁻)/c(HNO2)
c(NO2⁻)/c(HNO2) = 10⁰¹⁵ = 1.41
</span>
Answers-in-bold:
There are two common temperature scales. On the Fahrenheit scale, water freezes at 32 degrees. The Celsius scale divides the interval between the freezing and boiling points of water into 100 degrees.
Answer:
11.9g remains after 48.2 days
Explanation:
All isotope decay follows the equation:
ln [A] = -kt + ln [A]₀
<em>Where [A] is actual amount of the isotope after time t, k is decay constant and [A]₀ the initial amount of the isotope</em>
We can find k from half-life as follows:
k = ln 2 / Half-Life
k = ln2 / 27.7 days
k = 0.025 days⁻¹
t = 48.2 days
[A] = ?
[A]₀ = 39.7mg
ln [A] = -0.025 days⁻¹*48.2 days + ln [39.7mg]
ln[A] = 2.476
[A] = 11.9g remains after 48.2 days
<em />
Answer: -
0.2 Kg
Explanation: -
The equation used by Rhia for the carbon footprint measurement is
C = 0.2 B + 0.1 S
where S miles are by subway, B miles by bus and C is Kg of carbon dioxide.
From the equation we see the coefficient of B is 0.2.
Thus 0.2 Kg of carbon dioxide per mile the bus portion contributes to Rhia's carbon footprint.
Answer:
Atoms of elements at the top of a group on the periodic table are smaller than the atoms of elements at the bottom of the group. ... The valence electrons of the larger atoms are farther from the nucleus and are easier to remove, so the metals near the bottom are more reactive than those at the top.
