Cho sơ đồ chuyển hóa: CH₄ → C₂H₂ → C₂H₃Cl → PVC. Muốn tổng hợp 250 kg PVC theo sơ đồ trên thì cần V m³ khí thiên nhiên (ở đktc). Giá trị của V là?

(biết CH₄ chiếm 80% thể tích khí thiên nhiên và hiệu suất cả quá trình là 50%).

Chia sẻ

Một số câu hỏi khác có thể bạn quan tâm.

• Choose the word that has the underlined part pronounced differently from the rest: 

  son                   above                        convenience                        wonderful

• Choose the word that has the underlined part pronounced differently from the rest: 

  address                       important                      master                       embarrass

• Choose a word that has different stress pattern:

  service                    lobby                        weather                     receive

• Choose a word that has different stress pattern:

  polite                      problem                       arrive                       guitar

• Find a mistake in the four underlined parts of the sentence and correct it:

  I enjoy to talk with my classmates about their future plans.

• Find a mistake in the four underlined parts of the sentence and correct it:

  My daughter has been absent from school for three days because her illness.

• Choose the best answer for the following sentence:

  My brother’s new hobby is ______________ foreign coins.
  
  

• Choose the best answer for the following sentence:

  The children agreed _____________ the candy equally.
  
  

• Choose the best answer for the following sentence:

  Bob _____________ eating a whole bag of chocolate chip cookies before lunch.
  
  

• Choose the best answer for the following sentence:

  Mai is interested ____________ taking an art course.