Một hợp chất A có công thức dạng chung M\(_2\)X có tổng số hạt proton,electron,notron trong phân tử là 100 hạt ,số hạt mang điện nhiều hơn số hạt không mang điện là 20 hạt,nguyên tử M nhiều hơn nguyên tử X là 3 hạt proton.Xác định công thức cùa A

Làm ơn giúp mk vs

I.Complete the second sentences so that it has a similar meaning to the first sentences,using the word in bold and other words to complete each sentences.Do not change the word in bold

1.I won't go swimming if it rains tomorrow (unless)

➞..................................................................

2.He drives so carefully that he has had no acciddents (such)

➙............................................................................

3.Water boils at 100 degrees Celsius (if)

➞.................................................................

4. I'm sure it is Tom over there (must)

➞...........................................

5.They used to catch a bus to school (usually)

➞......................................................

đặt VT là A ta có:

\(3A=3\left(\frac{1}{1.4}+\frac{1}{4.7}+...+\frac{1}{x\left(x+3\right)}\right)=\frac{6}{19}\)

\(3A=1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+...+\frac{1}{x}-\frac{1}{x+3}\)

\(3A=1-\frac{1}{x+3}\)

\(\left(1-\frac{1}{x+3}\right):3\)

thay A vào VT ta đc\(\left(1-\frac{1}{x+3}\right):3=\frac{6}{19}\)

\(1-\frac{1}{x+3}=\frac{18}{19}\)

\(\frac{1}{x+3}=\frac{1}{19}\)

=>x+3=19

=>x=16

1.The film was boring

a;b =1;0

hoặc a;b =8;2

hoặc a;b =6;4

hoặc a;b =4;6

hoặc a;b =2;8

1.carelessly

2.disappeared

3.existence

4.imaginative

5.inventors

6.creation

7.unpleasant

8.safety

9.sleeplessness

10.widened

11.peaceful

12.unlaw

13.poverty

14.criminals

15.unhealthy

16.homeless

17.wealthy

18.death

19.streessful

20.physicians