Answer:
Group 8A
Explanation:
Group 8A elements are characterized by having full outermost s and p orbitals. These elements are also known as the noble gases or inert gases. They occupy the last group on the periodic table.
- They are known to have an outer shell configuration of ns² np⁶
- The configuration reveals that atoms of all the elements have completely filled orbitals in their outer shell sublevels.
- This accounts for the non-reactivity of elements in this group.
- Most of the elements in the group have high ionization energy and very low electron affinity values.
Some of the elements in this group are Neon, Argon, Krypton, Xenon, and Radon.
The amount of Mg(OH)2 present after the reaction is complete is 0.136 moles of Mg(OH)2.
The equation of the reaction is;
2HNO3(aq) + Mg(OH)2(aq) -------> Mg(NO3)2(aq) + 2H2O(l)
Number of moles of Mg(OH)2 = 8.00 g/58 g/mol = 0.138 moles
Number of moles of HNO3 = 0.205 M × 24.2 mL/1000 = 0.00496 moles
Given that;
2 moles of HNO3 reacts with 1 mole of Mg(OH)2
0.00496 moles of HNO3 reacts with 0.00496 moles × 1 mole /2 moles = 0.00248 moles of Mg(OH)2
Hence, Mg(OH)2 is the reactant in excess.
The amount of Mg(OH)2 remaining = Amount present - Amount reacted
Hence; 0.138 moles - 0.00248 moles = 0.136 moles of Mg(OH)2
Learn more: brainly.com/question/9743981
Inert gases are gases that don't react with other elements. What this means is that they won't combine with other elements, and trigger chemical reactions. I've posted a picture of the Periodic Table. Take a look at the VERY LAST row, all the way on the RIGHT side of the table. That row is made of up NOBLE GASES (He, Ne, Ar, Kr, etc.) Those noble gases are INERT. They are non-reactive.
Answer:
Explanation:
Approximately how many accidents occurred between 1965 and 1970 inclusive?
about 1800 accidents
about 2500 accidents
about 1200 accidents
about 1500 accidents
Answer:
C. Trp D. Phe E. Tyr
Explanation:
The concentration of a protein has a direct relation with absorbance of the protein in a UV spectrophotometer. The formula which relates concentration with absorbance is described as under:
A = ∈ x c x l
where, A = Absorbance
∈ = Molar extinction co-efficient
c = Concentration of absorbing species i.e. protein
l = Path length of light
Tryptophan (Trp), phenylalanine (Phe ) and tyrosine (Tyr) are three aromatic amino acids which are used to measure protein concentration by UV. It is mainly because of tryptophan (Trp), protein absorbs at 280 nm which gives us an idea of protein concentration during UV spectroscopy.
The table depicting the wavelength at which these amino acids absorb and their respective molar extinction coefficient is as under:
Amino acid Wavelength Molar extinction co-efficient (∈)
Tryptophan 282 nm 5690
Tyrosine 274 nm 1280
Phenylalanine 257 nm 570
In view of table above, we can easily see that Molar extinction co-efficient (∈) of Tryptophan is highest amongst all these 3 amino acids that is why it dominates while measuring concentration.
