This example is an controversial matter because melting an candle is considered as both physical change and chemical change because no new substances were made by melting an candle. The final answer is C.
A 1. 00 ml sample of an unknown gas effuses in 11. 1 min. an equal volume of h2 in the same apparatus under the same conditions effuses in 2. 42 minutes then the molar mass of the unknown gas is 41.9.
Molar mass of H2 = 2
Molar mass of unknown gas = ?
rate 1 = 11.1
rate 2 = 2.42
<h3>What is graham law? </h3>
Graham's law states that the rate of diffusion or effusion of a given gas is inversely proportional to the square root of its molar mass.
By apply graham law
Rate1/rate2 = sqrt(MW2/MW1)
![[\frac{rate1}{rate2} ]^{2} = \frac{MW2}{2} \\\\\\mw= 2[\frac{11.1}{2.42} ]^{2} \\\\= 20.97 X 2 \\\\= 41.9](https://tex.z-dn.net/?f=%5B%5Cfrac%7Brate1%7D%7Brate2%7D%20%5D%5E%7B2%7D%20%3D%20%5Cfrac%7BMW2%7D%7B2%7D%20%5C%5C%5C%5C%5C%5Cmw%3D%202%5B%5Cfrac%7B11.1%7D%7B2.42%7D%20%5D%5E%7B2%7D%20%5C%5C%5C%5C%3D%2020.97%20X%202%20%5C%5C%5C%5C%3D%2041.9)
Thus, we found that the molar mass of the unknown gas is 41.9.
Learn more about graham's law: brainly.com/question/12415336
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<span>c = speed of light = 3.00 x 10^5 km/s = 3.00 x 10^8 m/s
λ = wavelength of the microwave radiation = 3.50 cm = 0.035 m
f = frequency (in Hertz) = to be determined
f = c/λ = 3.00 x 10^8 m/s / 0.035 m
f = 8.57 x 10^9 Hz Frequency</span>
Answer: A: high ionization energies; high electron affinitlies.
Explanation: Covalent bonds are basically about sharing of electrons between two atoms to achieve that stable structure. They are formed between two atoms when both have similar tendencies to attract electrons to themselves (i.e., when both atoms have identical or fairly similar ionization energies and electron affinities). Covalent bonding usually occurs between two non-metals.
For effective and proper bonding, the two atoms involved in the covalent bonding exercise should be small and hungry for electrons. This is to enable the nuclei of both atoms to effectively attract and hold the shared electron(s) in place; hence, the need for high ionization energies & high electron affinities for a more effective covalent bonding.
