Question

. The no. of atoms in 60U of He (He = 4U) :

Answer 1

4 u of He have 1 atom.

60u will have = 60/4 = 15 atoms

Answer 2

Answer :

$\small{\sf{\red{Mass\:of\:He\:=\:4U}}}$

• Now , we have to find number of atoms in 60U of He .

→ Number of atoms in 4U = 1

→ Number of atoms in 1U = $\sf \dfrac{1}{4}$

→ Number of atoms in 60U = $\small{\sf {\dfrac{1}{4} \times 60\:=\: \dfrac{60}{4}\:=\:15}}$

▶ There are 15 atoms in 60U of He .

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' About He '

• He stands for Helium .

• He is a noble gas .

• Its atomic number is 2 .

• Mass of He = 4U .

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