Question

pls explain this problem step-by-step..


(From : class 9 ncert science textbook, [example 3.4] pg. no 42)​

Answer 1

we can use the following formulas to find the mass, no. of moles or no. of particles:-

i) no. of moles= given mass

molar mass

ii) no. of moles= no. of particles

avogadro's constant

iii) given mass = no. of particles

molar mass avogadro's constant

Therefore, from the above formulas we can say that:-

i) 0.5 mole of N2 gas (mass from mole of molecule)

ans:- given mass= x

molar mass= 14×2=28 g

no. of moles= 0.5 moles

we know that,

no. of moles= given mass

molar mass

0.5 = x

28

x= 0.5×28

x= 14 g

ii) 0.5 mole of N atoms (mass from mole of atom)

ans:- no. of moles = given mass

molar mass

0.5= x

14

x= 0.5×14

x= 7 g

iii) 3.011 × 10²³ no. of N atoms (mass from number)

ans:- given mass = number of particles

molar mass avogadro's constant

x = 3.011 × 10²³

14 6.022 ×10²³

x= 3.011 × 10²³ ×14

6.022× 10²³

x= 7 g

iv) 6.022 × 10²³ no. of N2 molecules (mass from no.)

ans:- given mass = number of particles

molar mass avogadro's constant

x = 6.022 ×10²³

28 6.022×10²³

x = 6.022 × 10²³ ×28

6.022 ×10²³

x = 28 g

Answer 2

Answer:

X=28 g this is answered