CH2O. You can reduce 8, 16, and 8 to 1, 2, and 1. You just simplify the numbers. When there is no number after an element, it means that there is one of them.
Answer:
Density of the copper = 8.94g/cm^3
Student A results = 7.3gm/cm^3 ,9.4 gm/cm^3 , 8.3gm/cm^3
Student B results = 8.4 gm/cm^3 , 8.8 gm/cm^3 , 8gm/cm^3
From the observations we conclude that
Student A's result is accurate but not precise as the trials noted are not close to each other.
Student B's result is accurate and precise as the trials noted are close to each other.
Mean density of student A = 7.3 + 9.4 + 8.3 /3 = 8.33gm/cm^3
Mean density of student B = 8.4 + 8.8 + 8 /3 = 8.4 gm/cm^3
both the densities of A and B are 0.5 away from the actual density.
<span>Hydrogen-2 has one neutron; hydrogen-1 has none</span>
Answer:
Explanation:
When an electron jumps from one energy level to a lower energy level some energy is released in the form of a photon.
The difference in energy between the two levels is the energy of the photon and that energy is related to the frequency of the photon by the Einstein - Planck equation:
Where,
- E = energy of the photon,
- h = 6.626×10⁻³⁴ J.s, Planck constant, and
- ν = frequency of the photon.
So, to find the frequency you must first find the energy.
The transition energy can be calculated using the formula:
Where E₀ = 13.6 eV ( 1 eV = 1.602×10⁻¹⁹ Joules) and n = 1,2,3,...
So, the transition energy between n = 4 and n = 3 will be:
- ΔE = - E₀ [ 1/4² - 1/3²] = - 13.6 eV [1/16 - 1/9] = 0.6611. . .eV
- ΔE = 1.602×10⁻¹⁹ Joules/eV × 0.6611... eV = 1.0591 ×10⁻¹⁹ Joules
Now you can use the Einstein - Planck equation:
- ν = 1.0591 ×10⁻¹⁹ J / 6.626×10⁻³⁴ J.s = 1.60×10¹⁴ s⁻¹ (rounded to 3 significant figures).
Answer:
312.731
Explanation:
it had a long answer but im sure ur teacher wanted u to round it
hope this helps!
~goldfishareswag/brianna
:)
