Question

which of the following has maximum number of molecules? a) 7gN2 b) 2gH2 c) 8gO2 d) 20gNO2

Answer 1

Explanation:

We know that no. of moles = given weight/gram molecular weight of the molecule.

Let us check all options,

1) 7g of N2

G.M.W (gram molecular weight) of N2 =14x2 = 28g

no.of moles = 7/28 = 1/4

2) H2 G.M.W = 2g

No. Of moles = 2/2 = 1

3) O2 G.M.W = 16x2 = 32g

No. Of moles = 8/32 = 1/4

4) NO2 G.M.W = 7+(16x2)= 39g

No of moles = 20/39

From this clearly we can say that 2g of H2 has most no. of moles compared to others.

Hope it helps:)

Answer 2

Answer:

B) 2gH2

Explanation:

A) 7gN2 has 0.25mole

B)2gH2 has 1mole

C) 8gO2 has 0.25mole

D)20gNO2 has 0.43mole

No. Of molecules is avagardo no. * no. Of moles