a) nAl= 0,2(mol)

PTHH: 4Al + 3 O2 -to-> 2 Al2O3

nO2= 3/4 . 0,2= 0,15(mol)

=>V(O2,đktc)=0,15.22,4=3,36(l)

Vkk(đktc)=5.V(O2,đktc)=3,36.5=16,8(l)

b) nAl=0,2(mol)

nO2=0,4(mol)

Ta có: 0,2/4 < 0,4/3

=> Al hết, O2 dư, tính theo nAl.

- Sau phản ứng có O2(dư) và Al2O3

nAl2O3= nAl/2= 0,2/2=0,1(mol)

nO2(dư)= 0,4- 0,2. 3/4=0,25(mol)

nếu thi thì tự làm...

k nha bn zaizzzzz

giờ này ai thi cơ chứ

1:I’m sorry if I’m spoiling but my favorite movie moment is the final battle between the Avengers and Thanos army in the Marvel movie: The Avenger: Endgame. This is the latest installment of The Marvel Cinematic Universe. It concludes a whole epic journey of lots of beloved characters in the movie.

The main plot line of the Avengers: Endgame is the fight between Thanos, a powerful alien , and the Earth protectors, the Avengers who consists of famous superheroes like Iron Man, Captain America, Black Widow, Hawkeye, the Hulk to name a few. Avengers: Endgame is a celebration of the characters , creatures and weapons that have been introduced throughout the Marvel cinematic Universe.

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The battle was my favorite moment of the entire movie because it’s the final fight that concludes the whole roller coaster ride from previous Marvel movies. As a hardcore fan , everything about Endgame was amazing and satisfying to watch. I will definitely watch it again even though it’s 3 hours long.

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a: \(A=\left(-6x^3+6x^3\right)+\left(2x^2+5x^2\right)+\left(5x-2x\right)-1=7x^2+3x-1\)

b: Hệ số cao nhất là 7

Hệ số tự do là -1

\(x^3+2x^2\left(4y-1\right)-4xy^2-9y^3-f\left(x\right)=-5x^3+8x^2y-4xy^2-9y^3\\ \Rightarrow\left(x^3+8x^2y+2x^2-4xy^2-9y^3\right)-f\left(x\right)=-5x^3+8x^2y-4xy^2-9y^3\\ \Rightarrow f\left(x\right)=x^3+8x^2y+2x^2-4xy^2-9y^3+5x^3-8x^2y+4xy^2+9y^3\\ \Rightarrow f\left(x\right)=6x^3+2x^2\)

1.B 2.C nha

B

C

1.B

2.C