Cho hợp chất X tác dụng với NaOH tạo ra khí Y làm xanh quỳ tím ẩm. Mặt khác chất X tác dụng với axit HCl tạo ra khí Z vừa làm vẩn đục nước vôi trong, vừa làm mất màu dung dịch brom. Chất X không tác dụng với dung dịch BaCl₂. Vậy chất X có thể là:

A. NH₄HCO₃

B. (NH₄)₂CO₃

C. (NH₄)₂SO₃

D. NH₄HSO₃

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the blanks

Owning a pet

The joys and tribulations of being a pet owner! During our lifetime most of us have some experience of either owning a pet or being in (7) _______ contact with someone who does. Is there such a things as “the ideal pet”? If so what characterizes the ideal pet? Various (8) _______ influence one’s choice of pet, from your reasons for getting a pet to your lifestyle. For example, although quite a few pets are relatively cheap to buy, the cost of upkeep can be considerable. Everything must be (9) _______ into account, from food and bedding, to vaccinations and veterinary bills. You must be prepared to (10) _______ time on your pet, which involves shopping for it, cleaning and feeling it. Pets can be demanding and a big responsibility. Are you prepared to exercise and housetrain an animal or do you prefer a more independent pet? How much spare room do you have? Is it right to lock an energetic animal into a confined space? Do you live near a busy road which may threaten the life of your pet? Pets such as turtles and goldfish can be cheap and convenient, but if you prefer affectionate pets, a friendly cat or dog would be more (11)

Điền ô số 10

A. take

B. waste

C. occupy

D. spend