Empirical formula of compound is XF3
Compound consist of 65% F
In 100g of compound there is 65 g of F
= 65 / 19 moles of Fluorine = 3.421 moles
So moles of X = 3.421 / 3 = 1.140 moles
And in 100 g X
consist of 35 g
So the molar mass of X = 35 / 1.140 = 30.71 g = 31
approximately
And it is the mass of phosphorus
So the empirical formula for the compound is PX3
Im not sure but it might be the last option: it gives reasons to be believed and trusted
The frequency of a wave is the number of wave cycles per second. this quantity is given the symbol ν and has units of s^–1 or hertz.
What is a wave ?
A wave is a dynamic disturbance of one or more quantities that propagates through time. When waves oscillate frequently around an equilibrium value at a certain frequency, they are said to be periodic.
What is a wave cycle ?
The wavelength is the measured distance in meters between two waves' peaks or troughs, which is referred to as a wave cycle. It's crucial to remember that the distance from peak to peak equals the distance from trough to trough. The length of time it takes a wave to complete one cycle is known as the wave's period.
Learn more about waves here:-
brainly.com/question/3639648
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