Answer:
I think it's B " Constraints are more important than criteria ".
Answer:
3 × 10^8 m/s
Explanation:
The wavelength, can be calculated by using the following formula;
λ = v/f
Where;
λ = wavelength (m)
v = velocity/speed of light (m/s)
f = frequency (Hz)
According to the provided information in this question, λ = 600nm i.e. 600 × 10^-9m, f = 5.00 x 10^14 Hz
Hence, using λ = v/f
v = λ × f
v = 600 × 10^-9 × 5.00 x 10^14
v = 6 × 10^-7 × 5.00 x 10^14
v = 30 × 10^(-7 + 14)
v = 30 × 10^ (7)
v = 3 × 10^8 m/s
Radioactive material obeys 1st order decay kinetics,
For 1st order reaction, we have
k =

where, k = rate constant of reaction
Given: Initial conc. 100, Final conc. = 6.25, t = 18.9 hours
∴ k =

= 0.1467 hours^(-1)
Now, for 1st order reactions: half life =

= 4.723 hours.
Molarity can be defined as the number of moles of solute in 1 L of solution.
M = n/V
Where M is the molarity of the solution (M or mol/L), n is the moles of the solute (mol) and V is the volume of the solution (L).
Here, solute is KF.
n = <span>0.250 mol
</span>V = 0.500 L
M = ?
By applying the formula,
M = 0.250 mol / 0.500 L
M = 0.500 mol/L
Hence, the molarity of KF solution is 0.500 mol/L.
Answer:
This atomic model has changed over time. Scientists used the model to make predictions. Sometimes the results of their experiments were a surprise and they did not fit with the existing model. Scientists changed the model so that it could explain the new evidence.
Explanation: