The 235u isotope (atomic mass = 235.00) undergoes fission when bombarded with neutrons. however, its natural abundance is only 0.72 percent. to separate it from the more abundant 238u isotope (atomic mass = 238.00), uranium is first converted to uf6, which is easily vaporized above room temperature. the mixture of 235uf6 and 238uf6 gases is then subjected to many stages of effusion. calculate how much more quickly 235uf6 effuses than 238uf6. give the answer as the ratio of rates of 235uf6 to 238uf6 to four decimal places.

So ²³⁵UF₆ effuses 1.0043 times faster than ²³⁸UF₆

Explanation:

The rate of effusion of two gases A and B can be expressed by Graham's law:

Where M is the molar mass, and in this case A is ²³⁵UF₆ while B is ²³⁸UF₆.

So now we calculate the molar mass of each mass:

²³⁵UF₆ ⇒235 + 6*19 = 349 g/mol

²³⁸UF₆ ⇒238 + 6*19 = 352 g/mol

Putting the data in Graham's law:

= 1.0043

So ²³⁵UF₆ effuses 1.0043 times faster than ²³⁸UF₆.

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.

it would be d. henry moseley

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