ใบงาน เคมีสำหรับข้อสอบเข้าพยาบาล พร้อมเฉลย

According to collision theory, what must happen for particles to react?

1. AThey must stay completely still next to each other
2. BThey must have the same mass
3. CThey must both be in the solid state at the same time
4. DThey must collide with enough energy and the right orientation

In a chemical reaction, what is the limiting reactant?

1. AThe reactant with the largest mass
2. BThe reactant that is left over at the end
3. CThe catalyst that controls the speed
4. DThe reactant that runs out first and stops the reaction

How many moles of oxygen atoms are in 1 mole of carbon dioxide, CO₂?

1. A0.5
2. B2
3. C1
4. D3

อะตอมของคลอรีน-37 มีโปรตอน 17 ตัว มีนิวตรอนกี่ตัว

1. A54
2. B17
3. C37
4. D20

How does dissolving salt in water affect the water's boiling point?

1. AIt makes the water boil at room temperature
2. BIt raises the boiling point slightly
3. CIt has no effect on the boiling point
4. DIt lowers the boiling point slightly

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

1. A−1
2. BIt equals the group number
3. C+1
4. D0

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

1. AThorium-234 (atomic number 90)
2. BProtactinium-234 (atomic number 91)
3. CThorium-238 (atomic number 90)
4. DPlutonium-242 (atomic number 94)

2090 J of heat is added to 50 g of water (specific heat 4.18 J/g·°C). By how much does its temperature rise?

1. A10 °C
2. B20 °C
3. C41.8 °C
4. D5 °C