265
your answer would be 265. Because the charge of +1 means there is one more proton then electron. So, 108 protons plus 157 neutrons gives you your mass number of 265.
Answer:
7.41 × 10⁻⁵
Explanation:
Let's consider the basic dissociation reaction of trimethylamine (CH₃)N).
(CH₃)N + H₂O = (CH₃)NH⁺ + OH⁻
According to Brönsted-Lowry, in this reaction (CH₃)N is a base and (CH₃)NH⁺ is its conjugate acid. The pKb for (CH₃)N is 9.87. We can calculate the pKa of (CH₃)NH⁺ using the following expression.
pKa + pKb = 14
pKa = 14 - pKb = 14 - 9.87 = 4.13
Then, we can calculate the acid dissociation constant for (CH₃)NH⁺ using the following expression.
pKa = -log Ka
Ka = antilog - pKa = antilog -4.13 = 7.41 × 10⁻⁵
The four metals that will not replace hydrogen in an acid are Cu, Ag, Au, Hg.
Explanation:
- As Copper Cu lies below the hydrogen, this is why it is less reactive and ca not replace Hydrogen from its compound.
- Silver Ag also lies below the hydrogen and therefore it is less reactive to displace Hydrogen.
- Gold Au becomes less reactive than Hydrogen due to its placement below Hydrogen acid.
- Mercury Hg is less reactive than Hydrogen