According to the passage, how can hydrogen be used to cut steel?

Câu hỏi :

According to the passage, how can hydrogen be used to cut steel?

A. By cooling the steel to a very low temperature

B. By cooling the hydrogen with oxygen to a very low temperature

C. By heating the steel to a very high temperature

D. By heating the hydrogen with oxygen to a very high temperature

* Đáp án

D

* Hướng dẫn giải

Dãn chứng: It releases more heat per unit of weight than any other fuel. In rocket engines, tons of hydrogen and oxygen are burned, and hydrogen is used with oxygen for welding torches that produce temperatures as high as 4,000 degrees F and can be used in cutting steel. 

Copyright © 2021 HOCTAP247