the atomic number of Cd is 48
atomic number gives the number of protons in the atom
elements in their ground state, the number of protons is equal to the number of electrons
therefore number of electrons is 48
the condensed electronic configuration is [Kr} 4d¹⁰ 5s²
the outermost energy shell is the 5th energy shell with 2 electrons in the 5s subshell.
Valence electrons are the electrons in the outermost energy shell that are involved in chemical bonding.
there are 10 electrons in the 4d subshell however 4th energy shell is not the outermost energy shell therefore these electrons are not regarded as valence electrons
In Cd there are 2 electrons in the outermost energy shell therefore Cd has 2 valence electrons.
answer is 2
Answer:
Steel is less malleable.
Explanation:
Steel is less malleable than the elements that make it because of the presence of carbon in it. Steel is an alloy of iron and carbon which is harder than iron because of the presence of carbon. Iron in its pure form is softer that able the atoms slip over one another. If carbon is added, they stop the iron atoms from sliding apart so easily. This makes the metal stronger and harder.
Answer:
A) pH = 8.11
B) pH = 7.96
Explanation:
The pH of buffer is calculated using Henderson Hassalbalch's equatio, which is
pKa = -logKa = -log(3.0 ✕ 10⁻⁸)
pKa = 7.5
[salt] = 0.667
[Acid] = 0.214
A) If the solution is halved it means the concentration of both salt and acid will be the same.
The volume will change
Number of moles of acid = molarity X volume = 0.214 X 25 = 5.35 mmol
Number of moles of salt = molarity X volume = 0.667 X 25 = 16.68 mmol
moles of NaOH added = molarity X volume = 0.100 X 10 = 1 mmol
These moles of NaOH will react with acid to give same amount of salt and thus the moles of acid will decrease
New moles of acid = 5.35 - 1 = 4.35
New moles of salt = 16.68 + 1 = 17.68
the new pH will be
B)
moles of HCl added = molarity X volume = 0.100 X 10 = 1 mmol
These moles of HCl will react with salt to give same amount of acid and thus the moles of salt will decrease
New moles of acid = 5.35 + 1 = 6.35
New moles of salt = 16.68 - 1 = 15.68
the new pH will be