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

Một dung dịch có pH bằng 3. Nó được mô tả là gì?

1. ABão hòa
2. BCó tính base
3. CCó tính acid
4. DTrung tính

Ở mực nước biển, nước tinh khiết sôi ở nhiệt độ nào?

1. A50 °C (122 °F)
2. B37 °C (98,6 °F)
3. C100 °C (212 °F)
4. D0 °C (32 °F)

What is a single covalent bond?

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

On an energy diagram, the products are at a lower energy than the reactants. What kind of reaction is shown?

1. AEndothermic
2. BExothermic
3. CReversible only
4. DNuclear

In the ideal gas law, PV = nRT, what does n stand for?

1. AThe number of molecules of gas
2. BThe density of the gas
3. CThe number of atoms per molecule
4. DThe number of moles of gas

Chất nào bị oxy hóa trong phản ứng 2Mg + O₂ → 2MgO?

1. AMagnesium, vì nó nhận electron
2. BOxygen, vì nó mất electron
3. CKhông chất nào thay đổi điện tích
4. DMagnesium, vì nó mất electron

Sugar is heated in a pan. Which observation shows that a chemical change, not just a physical change, has happened?

1. AIt gets hot to the touch
2. BIt melts into a clear, runny liquid that sets again when it cools
3. CIt turns black and gives off water vapour, leaving a solid that is no longer sweet
4. DThe crystals become smaller when crushed

In terms of bonds, why is a reaction exothermic?

1. AForming bonds always absorbs energy
2. BMore energy is released forming new bonds than is absorbed breaking old ones
3. CNo bonds are broken in exothermic reactions
4. DMore energy is absorbed breaking old bonds than is released forming new ones