The answer is c.) Rutherford model
Just add up the molar masses of each element.
Molar mass of C: 12.011 g/mol
The equation says C20, which means there are 20 carbon atoms in each molecule of Vitamin A. So, we multiply 12.011 by 20 to get 240.22 g/mol carbon.
Molar mass of H: 1.0079 g/mol
The equation says C30, which means there are 30 hydrogen atoms in each molecule of Vitamin A. So, we multiply 1.0079 by 30 to get 30.237 g/mol hydrogen.
Molar mass of O: 15.999 g/mol
The equation says O without a number, which means there is only one oxygen atom in each molecule of Vitamin A. So, we leave O at 15.999 g/mol.
Then, just add it up:
240.22 g/mol C + 30.237 g/mol H + 15.999 g/mol O = 286.456 g/mol C20H30O
So, the molar mass of Vitamin A, C20H30O, is approximately 286.5 g/mol.
The mass of water that contains 2.5×10²⁴ atoms of Hydrogen is 74.79 g
<h3>Avogadro's hypothesis </h3>
From Avogadro's hypothesis,
6.02×10²³ atoms = 2 g of H
Therefore,
2.5×10²⁴ atoms = (2.5×10²⁴ × 2) / 6.02×10²³
2.5×10²⁴ atoms = 8.31 g of H
<h3>How to determine the mass of water </h3>
- 1 mole of water H₂O = (2×1) + 16 = 18 g
- Mass of H in 1 mole of water = 2 g
2 g of H is present in 18 g of water.
Therefore,
8.31 g of H will be present in = (8.31 × 18) / 2 = 74.79 g of water.
Thus, 2.5×10²⁴ atoms of Hydrogen is present in 74.79 g of water.
Learn more about Avogadro's number:
brainly.com/question/26141731
The equation is:
Ca(OH)₂(s) + 2 HCl(aq) → CaCl₂(aq) + 2 H₂<span>O(l)
</span>
n=mass in g/M.M
15 g Ca(OH)₂ is n=15 g/ 74.1 g/mol=0.2024 mol of Ca(OH)₂
no. of mol of HCl:
n=0.5 mol/L*0.075L=0.0375 mol
This could react with 0.0375/2= 0.01875 mol of Ca(OH)₂ We have a lot more than that.
Therefore, HCl is the limiting reagent and determines how much CaCl₂ forms.
Based on the balanced reaction, 2 moles of HCl gives 1 mole of CaCl₂
no. of mol of CaCl₂= 0.0375/2= 0.01875 mol
mass in g=n*MM= 0.01875*111= 2.08 g
