Mass number of calcium isotopes
mass numberi the number of proton + neutron
number of proton for calcium is 20 regardless of isotopes
hence the only difference between calcium isotopes are rhe number of neutron
The control group is the type of tomato the plants are.
The independent variable is the type of music played.
The dependent variable is Plant A and B's growth.
His conclusion should be that music does not affect the growth of tomatoes.
He should make sure both plants were getting the same amount of water, soil, light, seed, and fertilizer so that can't affect the tomatoes in any way.
The answer is the letter C
Answer:
2.51 Angstroms
Explanation:
For a particle in a one dimensional box, the energy level, En, is given by the expression:
En = n²π² ħ² / 2ma²
where n is the energy level, ħ² is Planck constant divided into 2π, m is the mass of the electron ( 9.1 x 10⁻³¹ Kg ), and a is the length of the one dimensional box.
We can calculate the change in energy, ΔE, from n = 2 to n= 3 since we know the wavelength of the transition ( ΔE = h c/λ ) and then substitute this value for the expresion of the ΔE for a particle in a box and solve for the length a.
λ = 207 nm x 1 x 10⁻⁹ m/nm = 2.07 x 10⁻⁷ m ( SI units )
ΔE = 6.626 x 10⁻³⁴ J·s x 3 x 10⁸ m/s / 2.07 x 10⁻⁷ m
ΔE = 9.60 x 10⁻¹⁹ J
ΔE(2⇒3) = ( 3 - 2 ) x π² x ( 6.626 x 10⁻³⁴ J·s / 2π )² / ( 2 x 9.1 x 10⁻³¹ Kg x a² )
9.60 x 10⁻¹⁹ J = π² x( 6.626 x 10⁻³⁴ J·s / 2π )² / ( 2 x 9.1 x 10⁻³¹ Kg x a² )
⇒ a = 2.51 x 10⁻¹⁰ m
Converting to Angstroms:
a = 2.51 x 10⁻¹⁰ m x 1 x 10¹⁰ Angstrom / m = 2.51 Angstroms
Answeeeeer:
A. cell
Explanation:
Since A is the smallest in the chart, that would correspond to the cell because thats the smallest out of Tissue, Organ and Organism.
