Question

fast fast fast fast guys
ques.8, 9,10,11,12​

Answer 1

Answer:

8) The number of atoms present in a single molecule is termed as its atomicity. Atomicity of phosphorus is 4 and that of nitrogen is 7.

9)

1 mole = $6.02*10^{23}$

no. of atoms in 0.5 mole of C

$=0.5*(6.02*10^{23}) \\=\frac{1}{2}(6.02*10^{23})\\=3.01*10^{23}$

10)

$n$ = number of moles = 1.5 moles

$m$ = mass = ?

$M = M_{C}+M_{0_{2}} \\M = 12g/mole+(2*16g/mole)\\M = 12g/mole+32g/mole\\M = 44g/M$

$n=\frac{m}{M} \\m = n * M\\m = 1.5*44g/mole\\m = 66g$

11)

Atomic mass of Sodium(Na) = 23 g/mol

Atomic mass of Calcium(Cl) = 35.5 g/mol

Formula unit mass of Sodium cloride(NaCl)= 23 + 35.5 = 58.5 g/mol

12) $O_{2}$ means there are 2 atoms of oxygen in $O_{2}$ formula. 2O means there are 2 molecules of oxygen.

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