Dung dịch NaOH có pH = 12. Cần pha loãng dung dịch này bao nhiêu lần để thu được dung dịch NaOH mới có pH = 11?

A. 10.

B. 100.

C. 1000.

D. 10000.

Hiđroxit nào sau đây có tính lưỡng tính?

A. Al(OH)₃

B. Zn(OH)₂

C. Be(OH)₂

D. Be(OH)₂, Zn(OH)₂, Al(OH)₃, Cr(OH)₃.

Is this your the best refrigerator?

=> y² - x² = 117

=> (y - x)(y + x) = 117 = 1.117 = 3.39 = 9. 13 = (-1)(-117)= (-3)(-39) = (-9).(-13)

các gtri còn lại làm tương tự

1 employment

2 t0 read

3 useful

4 

study

studied

studies

studied

has studies

has studied

1 stop

2 are

1

1 you should do community service 

2 why don't listen to some music?

3 lan is a player volleyball for the school volley team

1 some people wok in hopital volunteers

2 are there any movies on cinema at the moment?

3 collecting stamps is lan's favorite pastime

4 nam spens the most time to lie on couch front of tv

5 now hoa is in music room and practicing playing the guitar

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