iron metal 10.4 mL HCl FeCl2 H2 density 7.86 g/mL FeCl2 gram

iron metal 10.4 mL HCl FeCl2 H2 density 7.86 g/mL FeCl2 gram

 

 

A sample of iron metal is placed in a graduated cylinder.

It is noted that 10.4 mL of water is displaced by iron.

The iron is then reacted with excess hydrochloric acid

to produce iron(II) chloride and hydrogen gas.

Given the density for iron is 7.86 g/mL,

how many grams of iron(II) chloride are produced in the reaction?

Fe(s) + 2HCl(aq) → FeCl2(aq) + H2(g)

 

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Fe의 몰질량 = 55.85 g/mol 이므로,

 

(10.4 mL) (7.86 g/mL) / (55.85 g/mol)

= (10.4) (7.86) / (55.85)

= 1.46 mol Fe

 

 

 

Fe + 2HCl → FeCl2 + H2

Fe : FeCl2 = 1 : 1 계수비(= 몰수비) 이므로,

1.46 mol Fe 반응 시,

생성되는 FeCl2의 몰수 = 1.46 mol

 

 

 

FeCl2의 몰질량 = 126.75 g/mol 이므로,

1.46 mol × (126.75 g/mol) = 185.055 g FeCl2

( 참고 https://ywpop.tistory.com/7738 )

 

 

 

답: 185 g