A nail made from the metal iron.
Answer:
Flerovium has 4 valence electrons in its outer shell. So, you did it right. All the dots are in the right place. Just fill in the dots and you should be good.
Hope that helps.
Answer:
False
Explanation:
The farther away a planet is, the colder it is.
1. The atomic number is equal to the number of protons in the nucleus, and the mass number is equal to the number of protons and neutros in the nucleus.
Therefore, to find the number of neutrons we must do mass number - atomic number, which equals 54.
Answer 1: a. 54
2. Atoms of a same element that have a different number of neutrons in the nucleus are called isotopes of an element.
Answer 2: d. Isotopes
3. Potassium has an electron configuration of
, meaning that the first 3 shells are full, and that the last shell (4th one) has only 1 electron.
Answer 3: c. Shells 1, 2 and 3 are full and shell 4 has one electron.
4. An atomic bond isn't a specific bond, it's just a term. Polar covalent and non-polar covalent bonds are strong bonds, which leaves us with the hydrogen bonds, which are indeed the weakest bonds out there.
Answer 4: a. Hydrogen bond
Hope it helped,
BiologiaMagister
Answer:
pH after the addition of 10 ml NaOH = 4.81
pH after the addition of 20.1 ml NaOH = 8.76
pH after the addition of 25 ml NaOH = 8.78
Explanation:
(1)
Moles of butanoic acid initially present = 0.1 x 20 = 2 m moles = 2 x 10⁻³ moles,
Moles of NaOH added = 10 x 0.1 = 1 x 10⁻³ moles
CH₃CH₂CH₂COOH + NaOH ⇄ CH₃CH₂CH₂COONa + H₂O
Initial conc. 2 x 10⁻³ 1 x 10⁻³ 0
Equilibrium 1 x 10⁻³ 0 1 x 10⁻³
Final volume = 20 + 10 = 30 ml = 0.03 lit
So final concentration of Acid = 
Final concentration of conjugate base [CH₃CH₂CH₂COONa]
Since a buffer solution is formed which contains the weak butanoic acid and conjugate base of that acid .
Using Henderson Hasselbalch equation to find the pH
![pH=pK_{a}+log\frac{[conjugate base]}{[acid]} \\\\=-log(1.54X10^{-5} )+log\frac{0.03}{0.03} \\\\=4.81](https://tex.z-dn.net/?f=pH%3DpK_%7Ba%7D%2Blog%5Cfrac%7B%5Bconjugate%20base%5D%7D%7B%5Bacid%5D%7D%20%20%5C%5C%5C%5C%3D-log%281.54X10%5E%7B-5%7D%20%29%2Blog%5Cfrac%7B0.03%7D%7B0.03%7D%20%5C%5C%5C%5C%3D4.81)