Phương trình hóa học nào dưới đây tỉ lệ số phân tử của các chất tham gia phản ứng là 1: 3 ?
A.$ 2F\text{e}+6{{H}_{2}}S{{O}_{4}}\to F{{\text{e}}_{2}}{{(S{{O}_{3}})}_{3}}+3S{{O}_{2}}+6{{H}_{2}}O $.
B.$ 2Al\,+\,3{{H}_{2}}S{{O}_{4}}\to A{{l}_{2}}{{(S{{O}_{4}})}_{3}}+3{{H}_{2}} $.
C.$ CaC{{O}_{3}}\xrightarrow{{{t}^{o}}}CaO+C{{O}_{2}} $.
D.$ F{{\text{e}}_{2}}{{O}_{3}}+6HCl\to 2F\text{e}C{{l}_{3}}+3{{H}_{2}}O $.

Cho sơ đồ của phản ứng sau :
$ F{{\text{e}}_{x}}{{(S{{O}_{4}})}_{y}}+Ba{{(OH)}_{2}}\to F\text{e(OH}{{\text{)}}_{y}}+BaS{{O}_{4}} $
Cặp x, y thỏa mãn là
A.3 và 2.
B.2 và 3.
C.2 và 2.
D.3 và 3.

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
The cats ……………… the mouse around the house.
A.are chasing
B.am chasing
C.is chasing
D.be chasing

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
I’m hungry, and ……………… is Nam.
A.As
B.Either
C.Neither
D.So

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
How ……………… is the ticket? – About $5.
A.many
B.rich
C.much
D.about

Choose the word whose underlined part differs from the other three in pronunciation
A.desire
B.noisy
C.sugar
D.present

Choose the word whose underlined part differs from the other three in pronunciation
A.shared
B.compared
C.repaired
D.catched

Choose the word whose underlined part differs from the other three in pronunciation
A.hurt
B.world
C.shirt
D.horizon

Choose the word whose underlined part differs from the other three in pronunciation
A.chin
B.cheap
C.school
D.each

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
They look forward to ______ out more about the architectural plan of the building
A.be found
B.found
C.find
D.finding