user-avatar
choaquyn
2 năm trước
Hợp chất A được cấu tạo bởi nguyên tố X hóa trị V với nguyên tố Oxi. Biết PTK của hợp chất A bằng 142 đvc . Hợp chất B được tạo ra bởi nguyên tố Y (hóa trị y, 1 ≤ y ≤ 3) và nhóm SO4, biết rằng phân tử khối của hợp chất A chỉ nặng bằng 0,355 lần phân tử hợp chất B. Tìm NTK củả nguyên tố X và Y. Viết CTHH của A và B
Thích Trả lời Chia sẻ

Các câu hỏi liên quan

Ex5.Put the following verbs into the past participle.And learn by heart. 1.Be- 1.Let- 2.Become- 2.Make- 3.Begin- 3.Mean- 4.Break- 4.Meet- 5.Bring - 5.Pay- 6.Build- 6.Put- 7.Buy- 7.Read- 8.Choose- 8.Rise- 9.Come- 9.Run- 10.Cots- 10.Say- 11.Cut- 11.See- 12.Do- 12.Send- 13.Dream- 13.Set- 14.Drink- 14.Shake- 15.Eat- 15.Shut- 16.Feel- 16.Sing- 17.Find- 17.Sit- 18.Forget- 18.Sleep- 19.Get- 19.Stand- 20.Give- 20.Swim- 21.Go- 21.Teke- 22.Have- 22.Teach- 23.Hear- 23.Tell- 24.Hold- 24.Think 25.Keep- 25.Wear- 26.Know- 26.Win- 27.Leam- 27.Wrin- Ex1.Put the correct verb form 0.She has never traveled(never/travel)by plane before 1.I_____(dream)of winning a medal for a long time. 2.She_______(not/see) much ò Vietnam,so she wanto to see more this year. 3._________you ever________(be)to a desert?No,never. 4.Van_____(throw)a surprise party for her boyfriend. 5.Where_____Stephen____(be)for the past2 days? Ex2.Underline the correct answer 0.His family hasn't contacted/didn't contact him for 5 years 1.She has seen/saw that movie more than5 times. 2.Stop complaining! You haven't stopped/stopped since you arrived. 3.We haven't found/didn't find any sign of life since we landed on Mars. 4.M.s Đó has never me to see her flast. 5.Congratulations!You have passed the exam.

Read the text and then decide if the statements are true or false. My name’s Helen and my husband’s name is Peter. We’ve got three children_ two sons and a daughter. Our sons’ names are Ian and Ben. They’re twins, but they aren’t identical. Ian’s got dark hair, but Ben’s hair is fair. Our daughter’s name’s Tracy. She’s eight years old. The boys are four. My father’s name is Frank and my mother’s name is Maureen. I’ve got two younger brothers, called Adam and Bobby. Adam is married. His wife’s name is Ulrike. She’s from Sweden and she’s got long, blond hair. They’ve got a baby daughter called Anna. So my parents have got four grandchildren_ two grandsons and two granddaughters. My husband’s got an older sister, but he hasn’t got any brothers. His sister’s name is Millie. She’s still single. 16. Frank is Ben’s grandfather. A. True B. False 17. Peter’s daughter has got black hair. A. True B. False 18. Adam is Bobby’s brother. A. True B. False 19. Millie hasn’t got a husband. A. True B. False 20. Bobby is married. A. True B. False 21. Peter hasn’t got any sisters. A. True B. False 22. Frank and Maureen’s granddaughters are twins. A. True B. False 23. Ben’s brother has got dark hair. A. True B. False

2018 © Loga - Không Ngừng Sáng Tạo - Bùng Cháy Đam Mê
Loga Team