Question

calculate number of moles and molecules of NH3 in volume 67.2 decimeter cube of it measured of STP​

Answer 1

NH3=67.2dm^3

No. Of moles = 67.2 ÷ molar volume

of gas

=67.2÷22.4

=3.0 mol

No. of = 3.0 × avocadro's constant

molecule. = 3.0 × 6.022 × 10^23

= 18.066 × 10^23 molecules

Answer 2

The number of moles of ammonia are 3 moles and it contains $1.806\times 10^{24}$

Explanation:

We are given:

Volume of ammonia = $67.2dm^3=67.2L$     (Conversion factor:  $1dm^3=1L$ )

At STP:

22.4 L of volume is occupies by 1 mole of a gas

So, 67.2 L of volume will be occupied by = $\frac{1}{22.4}\times 67.2=3mol$ of ammonia

According to mole concept:

1 mole of a gas contains $6.022\times 10^{23}$ number of molecules

So, 3 moles of ammonia will contain = $(3\times 6.022\times 10^{23})=1.806\times 10^{24}$ number of molecules

Learn more about STP and mole concept:

https://brainly.com/question/13265684

https://brainly.com/question/99540

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