Answer
2.7956 * 10^19 photons
Givens
- Wavelength = λ = 525 * 10^-9 meters [1 nmeter = 1*10^-9 meters]
- c = 3 * 10^8 meters
- E = ???
- W = 100 watts
- t = 1 second
- h= plank's Constant = 6.26 * 10^-34 J*s
Formula
E = h * c / λ
W = E / t
Solution
E = 6.26 * 10^-34 j*s * 3 * 10^8 m/s /525 * 10^-9 (m)
The meters cancel out. So do the seconds. You are left with Joules as you should be.
E = 3.577 * 10^-18 Joules
What you have found is the energy of 1 photon.
Now you have to find the Joules from the watts.
W = E/t
100 * 1 second = 100 joules
1 photon contains 3.577 * 10 ^ - 18 Joules
x photon = 100 joules
1/x = 3.577 * 10^-18 / 100 Cross multiply
100 = 3.577 * 10 ^ - 18 * x Divide both sides by 3.577 * 10 ^ - 18
100/3.577 * 10 ^ - 18 = 3.577 * 10 ^ - 18x / 3.577 * 10 ^ - 18
2.7956 * 10^19 photons = x
<h3><u>Answer;</u></h3>
a) It allows electrons to flow from the anode to the cathode.
<h3><u>Explanation</u>;</h3>
- <em><u>Voltaic cell is an electrochemical cell in which a spontaneous chemical reaction produces the flow of electrons</u></em>.
- Electrons are produced by the oxidation reaction occurring at the anode. Electrons flow through the conducting wire from the anode to the cathode. At the cathode these electrons are used to reduce copper(II) ions to copper atoms.
- <em><u>A conducting wire or a wire play connects the two electrodes allowing electrons to flow from the anode to the cathode</u></em>.
In france grapes are 1.83 euros per kilogram. What is the cost of grapes in dollars per pound if the exchange rate is 1.40 dollars per euro
1.83 euros x 1.40 = 2.56 dollars
1 pound = 0.454 kilogram
1.83 euros per kilogram = 2.56 x 0.454 = 1.16 dollars per pound
Answer:
If 51.8 of Pb is reacting, it will require 4.00 g of O2
If 51.8 g of PbO is formed, it will require 3.47 g of O2.
Explanation:
Equation of the reaction:
2 Pb + O2 → 2 PbO
From the equation of reaction, 2 moles of lead metal, Pb, reacts with 1 mole of oxygen gas, O2, to produce 2 moles of lead (ii) oxide, PbO
Molar mass of Pb = 207 g
Molar mass of O2 = 32 g
Molar mass of PbO = 207 + 32 = 239 g
Therefore 2 × 207 g of Pb reacts with 32 g of O2 to produce 2 × 239 g of PbO
= 414 g of Pb reacts with 32 g of O2 to produce 478 g of PbO
Therefore, formation of 51.8 g of PbO will require (32/478) × 51.8 of O2 = 3.47 g of O2.
If 51.8 of Pb is reacting, it will require (32/414) × 51.8 g of O2 = 4.00 g of O2
Explanation:
The states may differ depending on the reactions
