CaS is the empirical formula of the compound between calcium and sulphur that has the percent composition 55.6.
When percentages are given, we take a total mass of 100 grams.
Therefore the mass of each element is equal to the percentage given.
Mass of Ca = 55.6 g (given) of
S Mass = 44.4 g (100 - 55.6 = 44.4)
Step 1: Convert the given mass to moles.
moles Ca = given mass Ca / molar mass Ca
moles = 55.6 / 40 = 1.39 moles
mol S = specific mass S / molar mass S
mol = 44.4 / 32 = 1.39 mol
Step 2: Divide the molar ratio of each molar value by the smallest number of moles calculated.
For Ca = 1.39 / 1.39 = 1
For S = 1.39 / 1.39 = 1
The ratio of Ca : S = 1:1
Hence the empirical formula of the given compound will be CaS.
Learn more about empirical formula here : brainly.com/question/1496676
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The answer is <span>A. Speed=100 million m/s and frequency = 50 million Hz.</span>
Let's calculate for each choice the wavelength using the equation:
v = f × λ ⇒ λ = v ÷ f<span>
where:
v - the speed,
f - the frequency,
</span>λ - the wavelength.
A:
v = 100 000 000 m/s
f = 50 000 000 Hz = 50 000 000 1/s (Since f = 1/T, so units are Hz = 1/s)
⇒ λ = 100 000 000 ÷ 50 000 000 = 2 m
B:
v = 150 000 000 m/s
f = 1 500 Hz = 1 500 1/s
⇒ λ = 150 000 000 m/s ÷ 1 500 = 100 000 m
B:
v = 300 000 000 m/s
f = 100 Hz = 100 1/s
⇒ λ = 300 000 000 m/s ÷ 100 = 3 000 000 m
According to these calculations, the shortest wavelength is needed for choice A.
