<h3>The molecular formula of this protein : C₁₈H₄₂O₁₂N₆</h3><h3>Further explanation </h3>
The empirical formula is the smallest comparison of atoms of compound forming elements.
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
(empirical formula) n = molecular formula
The principle of determining empirical formula and molecular formula
- Determine the mass ratio of the constituent elements of the compound.
- Determine the mole ratio by dividing the elemental mass with the relative atomic mass obtained by the empirical formula
- Determine molecular formulas by looking for values of n
Find mol ratio for every component :
![\tt \dfrac{17.16}{12}=1.43](https://tex.z-dn.net/?f=%5Ctt%20%5Cdfrac%7B17.16%7D%7B12%7D%3D1.43)
![\tt \dfrac{3.17}{1}=3.17](https://tex.z-dn.net/?f=%5Ctt%20%5Cdfrac%7B3.17%7D%7B1%7D%3D3.17)
![\tt \dfrac{13.71}{16}=0.857](https://tex.z-dn.net/?f=%5Ctt%20%5Cdfrac%7B13.71%7D%7B16%7D%3D0.857)
N (r=14 g/mol) :
Mass of Nitrogen :
40.4-(17.16+3.17+13.71)=6.36 g
![\tt \dfrac{6.36}{14}=0.454](https://tex.z-dn.net/?f=%5Ctt%20%5Cdfrac%7B6.36%7D%7B14%7D%3D0.454)
C : H : O : N = 1.43 : 3.17 : 0.857 : 0.454 = 3.15 : 7 : 1.89 : 1=3:7:2:1
Empirical formula : C₃H₇O₂N
Molecular mass of protein :
![\tt \dfrac{40.4}{0.07141}=565.75](https://tex.z-dn.net/?f=%5Ctt%20%5Cdfrac%7B40.4%7D%7B0.07141%7D%3D565.75)
(C₃H₇O₂N)n=565.75
(12.3+1.7+2.16+14)n=565.75
(89)n=565.75
n=6.4≈6
so the molecular formula : C₁₈H₄₂O₁₂N₆
The volume of the 0.279 M Ca(OH)₂ solution required to neutralize 24.5 mL of 0.390 M H₃PO₄ is 51.4 mL
<h3>Balanced equation </h3>
2H₃PO₄ + 3Ca(OH)₂ —> Ca₃(PO₄)₂ + 6H₂O
From the balanced equation above,
- The mole ratio of the acid, H₃PO₄ (nA) = 2
- The mole ratio of the base, Ca(OH)₂ (nB) = 3
<h3>How to determine the volume of Ca(OH)₂ </h3>
- Molarity of acid, H₃PO₄ (Ma) = 0.390 M
- Volume of acid, H₃PO₄ (Va) = 24.5 mL
- Molarity of base, Ca(OH)₂ (Mb) = 0.279 M
- Volume of base, Ca(OH)₂ (Vb) =?
MaVa / MbVb = nA / nB
(0.39 × 24.5) / (0.279 × Vb) = 2/3
9.555 / (0.279 × Vb) = 2/3
Cross multiply
2 × 0.279 × Vb = 9.555 × 3
0.558 × Vb = 28.665
Divide both side by 0.558
Vb = 28.665 / 0.558
Vb = 51.4 mL
Thus, the volume of the Ca(OH)₂ solution needed is 51.4 mL
Learn more about titration:
brainly.com/question/14356286
The mass of unreacted zinc = 13 g
<h3>Further explanation
</h3>
The reaction equation is the chemical formula of reactants and products
A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reactants and products
Reaction
![\tt Zn+2HCl\Rightarrow ZnCl_2+H_2](https://tex.z-dn.net/?f=%5Ctt%20Zn%2B2HCl%5CRightarrow%20ZnCl_2%2BH_2)
mol ratio Zn : HCl = 1 : 2
![\tt mol=V\times M\\\\mol=0.1~L(100~cm^3)\times 2~mol/L\\\\mol=0.2](https://tex.z-dn.net/?f=%5Ctt%20mol%3DV%5Ctimes%20M%5C%5C%5C%5Cmol%3D0.1~L%28100~cm%5E3%29%5Ctimes%202~mol%2FL%5C%5C%5C%5Cmol%3D0.2)
![\tt \dfrac{1}{2}\times 0.2=0.1~mol](https://tex.z-dn.net/?f=%5Ctt%20%5Cdfrac%7B1%7D%7B2%7D%5Ctimes%200.2%3D0.1~mol)
![\tt 0.1\times 65=6.5~g](https://tex.z-dn.net/?f=%5Ctt%200.1%5Ctimes%2065%3D6.5~g)
![\tt 19.5-6.5=\boxed{\bold{13~g}}](https://tex.z-dn.net/?f=%5Ctt%2019.5-6.5%3D%5Cboxed%7B%5Cbold%7B13~g%7D%7D)