`PTK_(Ca(H_2PO_4)_2)=2[40+2(2+31+64)]=2. 234=468dvC`
`PTK_((NH_4)_2HPO_4)=2(14+4)+1+31+64=127dvC`
Phân tử khối:
- $Ca(H2PO_4)_2$: $40+(2+31+16.4).2=234$
- $(NH_4)_2HPO_4$: $(14+4).2+1+31+16.4=132$
Giúp mk với mk đang cần bài 3 nha
V. Đặt câu hỏi cho phần đc đánh dấu 1/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - She jogs '5 kilometers' a day. 2/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - It’s about '200 meters' from my school to the post office. 3/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - The dictionary is '200,000 dong'. 4/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - I’d like 'some local stamps and a phone card'. 5/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - Tim is 'my pen pal in England'. 6/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - I need a phone card 'to phone my parents'. 7/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - Mr. Viet is 'a farmer'. 8/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - Lan often 'goes to the library' in her free time. 9/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - My mother 'is cooking' in the kitchen at the moment. 10/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - Nam likes playing 'soccer' after school. 11/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - I go to the movies 'twice a month'. 12/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - Hoa will be 'twelve' on her next birthday. 13/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - Nam’s favorite subject is 'Electronics'. 14/ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - The shoes cost '50,000 dong'.
a) Viết các số đo thể tích: Ba phần tám đề-xi-mét khối; Không phẩy chín trăm mười chín mét khối.
Không cần làm hết đâu ạ, chỉ cần làm 1 trong 3 bài là được
giúp ạ :( Tom didn’t learn hard enough to pass the final English exam. (Use the conditional sentence) If Tom______________________________________________________________.
tính bằng cách hợp lý nhất 36.23+62.23.46
Put the questions to the underlined parts in the following. 1. Linh is reading books in the library. >.............................................................? 2. The boys are playing in the garden. >.............................................................? 3. We mustn't drink and eat in the classroom. ->.........................................................................? 4. We sometimes stay up late on Saturday night. ->...............................................................................? 5. Many girls do aeribics at the weekend. ->..................................................................?
chỉ mik cách làm tobokki từ bột mì với
TÌm số mol của các lượng chất sau đây a, 8g NaOH b, 23,2g Fe3O4
Viết các đa thức sau dưới dạng bình phương của 1 tổng hoặc 1 hiệu (2x+3y)+2.(2x+3y)+1 9x^2-6x+1
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