MgO 25.0 g Mg react O2 gram

MgO 25.0 g Mg react O2 gram

 

 

Magnesium metal burns in oxygen to form magnesium oxide, MgO.

a) Write a balanced equation for the reaction.

b) How many grams of oxygen are needed to react with 25.0 g of Mg?

How many grams of MgO will result?

 

 

 

a) Write a balanced equation for the reaction.

 

Mg + O2 → MgO (unbalanced)

 

2Mg + O2 → 2MgO (balanced)

 

 

 

 

b) How many grams of oxygen are needed to react with 25.0 g of Mg?

How many grams of MgO will result?

 

> Mg의 몰질량 = 24.305 g/mol

> O2의 몰질량 = 32.00 g/mol

> MgO의 몰질량 = 40.30 g/mol

 

 

 

질량비로 계산하면,

( 참고: 질량비로 계산 https://ywpop.tistory.com/22115 )

 

2Mg : O2 = 2(24.305) : 32.00 = 25.0 g : ? g

 

? = 32.00 × 25.0 / (2(24.305)) = 16.4575...

= 16.5 g O2

 

 

 

Mg : MgO = 24.305 : 40.30 = 25.0 g : ? g

 

? = 40.30 × 25.0 / 24.305 = 41.452376...

= 41.5 g MgO

 

 

 

 

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