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

Nguyên tố nào có ký hiệu K?

1. ACalcium
2. BKrypton
3. CPotassium
4. DCarbon

What is gamma radiation?

1. AA fast stream of protons from the nucleus
2. BA stream of helium nuclei with a positive charge
3. CA slow-moving electron
4. DHigh-energy electromagnetic radiation with no mass or charge

What is a single covalent bond?

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

What is the oxidation number of an element in its uncombined (elemental) form, such as Fe or O₂?

1. AIt equals the group number
2. B0
3. C+1
4. D−1

How does a mixture of iron filings and sulfur powder differ from the compound iron sulfide?

1. AThe mixture is formed by a chemical reaction between the two elements
2. BThe mixture has a fixed ratio of iron to sulfur
3. CThe mixture can be separated physically, for example with a magnet
4. DThe compound keeps the magnetic properties of iron

When a nucleus emits an alpha particle, how do its mass number and atomic number change?

1. AMass number stays the same and atomic number rises by 1
2. BNeither changes
3. CMass number falls by 4 and atomic number falls by 2
4. DMass number falls by 2 and atomic number falls by 4

Many ethene (C₂H₄) molecules join together to form poly(ethene), a plastic. What type of reaction is this?

1. ACombustion, in which ethene reacts with oxygen
2. BCondensation polymerisation, in which a water molecule is released at each new link
3. CHydrolysis, in which water breaks each monomer apart
4. DAddition polymerisation, in which the C=C double bonds open up to link the monomers

Using PV = nRT with R = 0,082 L·atm/(mol·K), how many moles of gas are in 24,6 L at 1 atm and 300 K?

1. A1 mol
2. B0,5 mol
3. C2 mol
4. D300 mol