Phiếu bài tập Hóa học cho kỳ thi đầu vào điều dưỡng có đáp án

What is a single covalent bond?

1. AOne pair of electrons shared between two atoms
2. BOne electron transferred from one atom to another
3. CThe attraction between two oppositely charged ions
4. DTwo pairs of electrons shared between two atoms

What is a beta particle?

1. AA high-energy electron released from a nucleus
2. BA neutron that leaves the nucleus
3. CA helium nucleus with two protons and two neutrons
4. DA wave of visible light

What should a student always wear to protect the eyes when working with chemicals?

1. ASunglasses
2. BSafety goggles
3. CReading glasses
4. DContact lenses

Vì sao khí hiếm hiếm khi phản ứng?

1. AChúng hoàn toàn không có electron
2. BTất cả chúng đều phóng xạ
3. CLớp electron ngoài cùng của chúng đã đầy
4. DNguyên tử của chúng lớn hơn nhiều so với các nguyên tử khác

Which coefficients balance __Na + __Cl₂ → __NaCl?

1. A1, 2, 1
2. B2, 2, 1
3. C2, 1, 2
4. D1, 1, 1

At 20 °C, about 36 g of NaCl dissolves in 100 g of water. If 50 g of NaCl is stirred into 100 g of water at 20 °C, what happens?

1. AAll 50 g dissolves
2. BAbout 14 g dissolves and about 36 g stays undissolved
3. CNone of the salt dissolves
4. DAbout 36 g dissolves and about 14 g stays undissolved

Making ammonia (N₂ + 3H₂ ⇌ 2NH₃) is exothermic. A low temperature would give a higher yield, yet factories use a moderately high temperature. Why?

1. AThe catalyst only works when the reaction is endothermic
2. BAt low temperatures the reaction is too slow to be useful
3. CHigher temperatures shift the equilibrium toward more ammonia
4. DLow temperatures would make the ammonia explode

Phản ứng nào sau đây là phản ứng trung hòa?

1. AZn + CuSO₄ → ZnSO₄ + Cu
2. BCH₄ + 2O₂ → CO₂ + 2H₂O
3. C2H₂O → 2H₂ + O₂
4. DH₂SO₄ + 2KOH → K₂SO₄ + 2H₂O