<span>First we need to find the energy of one photon with a wavelength of 589 nm.
E = hc / wavelength
E = (6.63 x 10^{-34} J s)(3 x 10^8 m/s) / (589 x 10^{-9} m)
E = 3.3769 x 10^{-19} Joules
To find N, the number of photons, we need to divide the total energy by the energy of each photon.
N = 623000 J / 3.3769 x 10^{-19} Joules
N = 1.84 x 10^{24} photons
There are 1.84 x 10^{24} photons in the burst of yellow light.</span>
Answer:
7.37 mL of KOH
Explanation:
So here we have the following chemical formula ( already balanced ), as HNO3 reacts with KOH to form the products KNO3 and H2O. As you can tell, this is a double replacement reaction,
HNO3 + KOH → KNO3 + H2O
Step 1 : The moles of HNO3 here can be calculated through the given molar mass ( 0.140 M HNO3 ) and the mL of this nitric acid. Of course the molar mass is given by mol / L, so we would have to convert mL to L.
Mol of NHO3 = 0.140 M
30 / 1000 L = 0.140 M
0.03 L = .0042 mol
Step 2 : We can now convert the moles of HNO3 to moles of KOH through dimensional analysis,
0.0042 mol HNO2
( 1 mol KOH / 1 mol HNO2 ) = 0.0042 mol KOH
From the formula we can see that there is 1 mole of KOH present per 1 moles of HNO2, in a 1 : 1 ratio. As expected the number of moles of each should be the same,
Step 3 : Now we can calculate the volume of KOH knowing it's moles, and molar mass ( 0.570 M ).
Volume of KOH = 0.0042 mol
( 1 L / 0.570 mol )
( 1000 mL / 1 L ) = 7.37 mL of KOH
2 Al + 3 H₂SO₄ = Al₂(SO₄)₃ + 3 H₂
2 moles Al -------- 3 moles H₂SO₄
4.4 moles Al ------ ?
moles H₂SO₄ = 4.4 x 3 / 2
moles H₂SO₄ = 13.2 / 2
= 6.6 moles of H₂SO₄
hope this helps!
The absolute value of any number is positive
Answer:
<h3>The answer is 11 g/mL</h3>
Explanation:
The density of a substance can be found by using the formula

From the question
mass = 3025 g
volume = 275 mL
We have

We have the final answer as
<h3>11 g/mL</h3>
Hope this helps you