Hi!
The correct option would be 3.85x10^(24)
To find the number of atoms in 250g of potassium, we need to first calculate the number of atoms in
1 mole of Potassium = 39g which contains 6.022x10^(23) atoms of K
<em>(Avogadro's constant value for the amount of molecules/atoms in one mole of any substance)</em>
<em>Solution</em>
So as 39g of Potassium contains 6.022x10^(23) K atoms
1g of Potassium would contain 6.022x10^(23) / 39 = 1.544 x10^(22) atoms
So 250g of Potassium would contain 1.544x10^(22) x 250 = 3.86x10^(24) atoms
Answer:
The concentration of species in 500 mL of a 2.104 M solution of sodium sulfate is 4.208 M sodium ion and 2.104 M sulfate ion. (option E)
Explanation:
Step 1: Data given
Volume = 500 mL = 0.500 L
The concentration sodium sulfate = 2.104 M
Step 2: The equation
Na2SO4 → 2Na+ + SO4^2-
For 1 mol Na2SO4 we have 2 moles sodium ion (Na+) and 1 mol sulfate ion (SO4^2-)
Step 3: Calculate the concentration of the ions
[Na+] = 2*2.104 M = 4.208 M
[SO4^2-] = 1*2.104 M = 2.104 M
The concentration of species in 500 mL of a 2.104 M solution of sodium sulfate is 4.208 M sodium ion and 2.104 M sulfate ion. (option E)
Answer:
11.2 M → [HCl]
Explanation:
Solution density = Solution mass / Solution volume
35.38 % by mass, is the same to say 35.38 g of solute in 100 g of solution.
Let's determine the moles of our solute, HCl
35.38 g . 1 mol/36.45 g = 0.970 moles
Let's replace the data in solution density formula
1.161 g/mL = 100 g / Solution volume
Solution volume = 100 g / 1.161 g/mL → 86.1 mL
Let's convert the volume to L → 86.1 mL . 1L / 1000 mL = 0.0861 L
Molarity (M) → mol/L = 0.970 mol / 0.0861 L → 11.2 M