Question

下列分子數由少至多的順序是______，質量由小到大的順序______．
①6g氫氣     ②2mol氨氣     ③4℃時 9mL水④1.204×10²³個硫酸分子      ⑤標準狀況下5.6LCO₂．

Answer 1

①6g氫氣，分子數N=nN_A=

m

M

×NA=

6g

2g/mol

×NA=3NA，質量是6g．
②2mol氨氣，分子數N=nN_A =2N_A，m=nM=2mol×17g/mol=34g．
③4℃時 9mL水，其質量是9g．分子數N=

n

M

×NA=

9g

18g/mol

×NA=0.5N _A
④1.204×10²³個硫酸分子，分子數N=0.2N_A，質量m=

N

NA

×M=

0．2NA

NA

×98g/mol=19.6g
⑤標準狀況下5.6LCO₂，，分子數N=

V

Vm

×NA=

5.6L

22.4L/mol

×NA=0.25N_A，m=

V

Vm

×M=

5.6L

22.4L/mol

×44g/mol=11g
故答案為：④⑤③②①；①③⑤④②