Answer:
I think its the first one but im not 100%
Explanation:
Answer: C10H8 + 12O2 ----> 10CO2 + 4H2O
Explanation:
To balance this, we have to make sure that the same number of atoms exist at both sides (Conservation of energy)
Note:The reaction is exothermic, giving off heat energy.
Left hand side: C= 10,
H=8,
O= 2×12=24
Right hand side: C= 10×1=10,
H= 4×2=8,
O=10×2=20 (for 10CO2) and 4×1=4 (All equal to 24)
With the above analysis, it is clear that numbers had to be added to molecules to get an equal number of atoms for both sides.
Answer:
600 mL
Explanation:
The volume of 10% acid solution used to make the mixture = 200 L
Let the volume of 30% acid solution used to make the mixture = x mL
Total volume of the mixture = (200+ x) mL
For 10% acid solution:
C₁ = 10% , V₁ = 200 mL
For 30% acid solution :
C₂ = 30% , V₂ = x mL
For the resultant solution of sulfuric acid:
C₃ = 25% , V₃ = (200 + x) mL
Using
C₁V₁ + C₂V₂ = C₃V₃
10×200 + 30×x = 25×(200 + x)
Solving for x,
x = 600 mL
<u>600 milliliters of solution Y must be added to 200 milliliters of solution X to create a solution that is 25 percent alcohol by volume.</u>
A period in the periodic table is a row of chemical elements. All elements in a row have the same number of electron shells
Answer:
the wavelength, in nm, of the photon is 487.5 nm
Explanation:
Given:
n = 4 (excited)
n = 2 (relaxes)
Question: Calculate the wavelength, in nm, λ = ?
First, it is important to calculate the energy of the electron when it excited and then when it relaxes.
(excited)
(relaxes)
The change of energy
ΔE = E₁ - E₂=-0.85 - (-3.4) = 2.55 eV = 4.08x10⁻¹⁹J
For a photon, the wavelength emitted
Here
h = Planck's constant = 6.63x10⁻³⁴J s
c = speed of light = 3x10⁸m/s
Substituting values: