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

How does increasing the concentration of a reactant in solution usually affect the reaction rate?

1. AThe rate stays the same
2. BThe rate decreases
3. CThe rate increases
4. DThe reaction stops

What is the SI unit of temperature?

1. ADegree Fahrenheit
2. BDegree Celsius
3. CKelvin
4. DJoule

Which state of matter has a fixed volume but takes the shape of its container?

1. APlasma
2. BLiquid
3. CGas
4. DSolid

Why does stirring help a solid dissolve faster?

1. AIt brings fresh solvent into contact with the solid's surface
2. BIt increases the amount of solute that can dissolve in total
3. CIt raises the temperature of the solvent by friction a great deal
4. DIt turns the solid into a liquid

A piece of metal has a density of 8 g/cm³ and a volume of 5 cm³. What is its mass?

1. A0,625 g
2. B40 g
3. C1,6 g
4. D13 g

What is the oxidation number of sulfur in H₂SO₄?

1. A+2
2. B−2
3. C+4
4. D+6

Uranium-238 (atomic number 92) undergoes alpha decay. Which nucleus is formed?

1. AThorium-234 (atomic number 90)
2. BPlutonium-242 (atomic number 94)
3. CProtactinium-234 (atomic number 91)
4. DThorium-238 (atomic number 90)

Which statement correctly distinguishes a scientific law from a scientific theory?

1. ALaws apply only to chemistry, theories only to biology
2. BA law describes what happens; a theory explains why it happens
3. CA theory becomes a law once it is proved
4. DA law is only a guess, while a theory is a proven fact