Answer:
The concentration of the copper sulfate solution is 83 mM.
Explanation:
The absorbance of a copper sulfate solution can be calculated using Beer-Lambert Law:
A = ε . c . <em>l</em>
where
ε is the extinction coefficient of copper sulfate (ε = 12 M⁻¹.cm⁻¹)
c is its molar concentration (what we are looking for)
l is the pathlength (0.50 cm)
We can use this expression to find the molarity of this solution:
Answer:
The answer to your question is
1.- 1.686 x 10²⁴ atoms
2.- 0.25 moles
Explanation:
1.-
1 mol ---------------- 6.023 x 10²³ atoms
2.8 moles ---------- x
x = (2.8 x 6.023 x 10²³) / 1
x = 1.686 x 10²⁴ atoms
2.- 1 mol ------------------ 6.023 x 10 ²³ molecules
x moles ------------- 1.50 x 10²³ molecules
x = (1.50 x 10²³ x 1) / 6.023 x 10²³
x = 0.25 moles
Answer:
C
Explanation:
Only this choice is applicable and correct.
The inter-molecular forces of attraction between the molecules must have been broken (overcome) before the molecules can gain an increase in the kinetic energies between them.
Heat of vaporization of water will be required as water is already at it's boiling point thus heat required will be 540*10=5400 cal
The molarity of the stock solution of luminol is 1.2 M
<u><em>calculation</em></u>
step 1: find the moles of luminol using (moles= mass/molar mass) formula
molar mass of Luminol= 177 g/mol
moles is therefore= 16.0 g/ 177 g/mol=0.0904 moles
Step 2: find the molarity using (molarity= moles/volume in liters) formula
convert Ml into liters = 75.0/1000= 0.075 L
molarity is therefore= 0.0904 moles/ 0.075 L= 1.2M
