câu 1: Cho 5,6 lít hỗn hợp etan và propilen (đktc) đi chậm qua dung dịch brom dư. Sau phản ứng khối lượng bình brom tăng thêm 6,3 gam. Số mol etan và propilen trong hỗn hợp lần lượt là. câu 2: Cho các chất sau: pent−1−in; etilen; etin; propin; but−2−in; isopren. Số chất tạo kết tủa khi tác dụng với dung dịch AgNO 3 trong NH 3 ?

Tìm các số nguyên x và y: x/y=2/7

Làm hộ mik nha!!!!!!!!!!;;!!!!!!!

Bạn nào giúp mk bài tập đạo hàm với mk đang cần gấp

giúp e với ạ e đag cần gấp cảm ơn ạ

5x(3x-2)-2(3x-2)=0 có ai bik giúp mik nha

II. Chia động từ ở thì Tương lai đơn hoặc tương lai gần. 1. “I am not going to play soccer this afternoon.” “What ______ you_____________ (do)?” 2. Look at those clouds. It __________________________ (rain) 3. I feel terrible. I think I ______________________(be) sick. 4. “Tom had an accident last night.” “Oh! I see I_____________ (visit) him” 5. I think Li Li ________________ (like) the present we bought for her. 6. We ___________________ visit our grand parents this evening. 7. “Nam phoned you while you were out.” “OK. I ________________(call) him back.” 8. I am tidy the room. I _________________________ (hold) my birthday tonight. 9. I ____________________ (see) the movie Dream City this evening. 10. “Don’t play soccer here again.” “I’m sorry. I _______________ (do) that again.

Tính giá trị của biểu thức A=(x mũ 2-1).(x mũ 2-3).(x mũ 2-5)......(x mũ 2-99) tại x=5

Ñoát chaùy khí axeâtylen (C2H2) trong khí oxi sinh ra khí cacbonic vaø hôi nöùôùc .Daãn hoãn hôïp khí vaøo dung dòch nöôùc voâi trong ( Ca(OH)2) thì thu ñöôïc chaát keát tuûa canxicacbonat (CaCO3) .Vieát caùc PTPÖ xaûy ra .(BiÕt r»ng khÝ cacbonic lµm ®ôc n­íc v«i trong cßn h¬i n­íc th× kh«ng)

A HEALTHY LIFESTYLE The Thomson family tries to eat healthy meals for a very long time but they find it difficult to keep it up. Mr. and Mrs. Thomson work long hours at the hospital. They feel very tired whenever they arrive home. They have three young children: David is eight, Anna is six and a baby is one. It is difficult for me family to cook healthy meals every day. So they order fast food such as pizza, French fries or hamburger for many months. This is a bad routine homemade meals. At first, they feel so tired, but David helps them prepare the meals, so now they don't feel tired any more . They feel very excited when eating homemade meals every day. 1. What does the Thomson family try to do for a very a long time? 2. Where do Mr and Mrs. Thomson work? 3. How many kids do they have? 4. How old is David? 5. Why does the family order fast food every day? 6. Who helps Mr. and Mrs. Thomson pepare homemade meals? 7. Where do Mr. and Mrs. Thomson buy food to make homemade meals? 8. How do they feel about eating homemade meals now?