The number of particles in one mole is given be Avagadro's number <span>6.022×10^23
Multiply by number of moles.
3 ×10^-21 mol * 6.022 ×10^23 molecules/mol = </span><span>1,807 molecules
(rounded to nearest whole number)
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The answer is wedge to your answer
Its hybridization would be sp because Be only has 2 covalent bonds with Cl
Mercury expands when it is heated. This process is called thermal expansion.