Answer:- 
Explanations:- Alkanes are non polar molecules as these only have carbons and hydrogens. Electron negativity difference of C and H is very low and it makes them non polar. These have weaker London dispersion forces.
The forces of attraction becomes stronger in alkanes as the number of carbon increases because the surface area as well as molecular weight of the alkanes increases with an increase in number of carbons.
Butane has four carbons, propane has three carbons, ethane has two and methane has only one carbon, So, the strongest to weakest order of inter molecular forces is butane > propane > ethane > methane .
The electron is travelling with a velocity of 1.123 × 10⁷m/s if it has a wavelength of 8.20 km.
<h3>How to calculate velocity of an electron?</h3>
The velocity at which an electron travels can be calculated using the following formula:
λ = h/mv
Where;
- H = Planck's constant
- m = mass of electron
- v = velocity of electron
- λ = wavelength
- Planck's constant (h) = 6.626 × 10−³⁴ J⋅s.
- mass of electron (m) = 9.109 × 10−³¹ kg
- wavelength = 8200m
8200 = 6.626×10−³⁴ / 9.109 × 10−³¹V
8200 = 7.3 × 10-⁴V
V = 8200 ÷ 7.3 × 10-⁴
V = 1.123 × 10⁷m/s
Therefore, the electron is travelling with a velocity of 1.123 × 10⁷m/s if it has a wavelength of 8.20 km.
Learn more about velocity at: brainly.com/question/13171879
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Answer:
3.955*10^48
Explanation:
1 mole of a substance gives 6.02*10^23/6.57*10^24 will give x then cross multiply the answer. is 3.955*10^48
Use the rule of 3 simple
50 g mean 100% 0,1895 mean x% cross multiplie and calcule the x value x = 0,1895*100/50 = ?%
