HOC24
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Almost everything that we see around us is the gift of science and technology. Be it the smart-phones, fan, wheel, vehicles, etc., everything is the result of science and technology. It helps us save time & money – Various contributions of science and technology have helped us save time and money. Various objects and devices like computers, modes of transport, washing machines or just anything else help us save our time and money. Science & technology have made significant contribution in the education field as well. With the help of internet, we do not only get immense knowledge on science and other subjects, but we also get to stay connected with our friends and family, continuously. It helps us live a better life. Technology has benefited us in receiving those treatments through various ways and devices like X-ray, scan machines, operation devices, pacemaker and much more! Nowadays, online doctor and other things that help us maintain good health and life. Henceforth, with the help of science and technology, let’s make world a better place, for you, me & the entire human race!
Đun nóng hợp chất hữu cơ X (CH6O3N2) với NaOH thu được 2,24 lít khí Y có khả năng làm xanh giấy quỳ tím ẩm. Khối lượng muối khan thu được sau phản ứng là
A. 8,2 gam
B. 8,5 gam
C. 6,8 gam
D. 8,3 gam
“I will help you with the housework”, Mai said.
A. Mai promised to help me with the housework
B. Mai asked me to help her with the housework
C. Mai begged to help me with the housework
D. Mai insisted on helping me with the housework
Trộn 300ml dung dịch HCl 0,05M với 200ml dung dịch Ba(OH)2 nồng độ a mol/l thu được 500ml dung dịch có pH = x. Cô cạn dung dịch sau phản ứng thu được 1,9875 gam chất rắn. Giá trị của a và x lần lượt là