ใบงาน เคมีสำหรับข้อสอบเข้าพยาบาล พร้อมเฉลย

What is a molecule?

1. AA mixture of two different elements
2. BTwo or more atoms held together by covalent bonds
3. CA single atom with a positive charge
4. DThe nucleus of an atom

Elements in the same period of the periodic table have the same number of what?

1. AProtons
2. BOccupied electron shells
3. CValence electrons
4. DNeutrons

What is the name of the polyatomic ion NH₄⁺?

1. AAmmonium
2. BNitrate
3. CNitride
4. DAmmonia

สารประกอบใดเกิดขึ้นระหว่างแคลเซียม (Ca²⁺) และคลอรีน (Cl⁻)

1. ACa₂Cl₃
2. BCaCl
3. CCaCl₂
4. DCa₂Cl

What is nuclear fission?

1. AThe loss of electrons from an atom
2. BThe joining of two light nuclei to form a heavier nucleus
3. CThe splitting of a heavy nucleus into smaller nuclei
4. DThe burning of uranium in oxygen

How does a catalyst speed up a reaction?

1. AIt adds extra reactant to the mixture
2. BIt raises the temperature of the reactants so they move faster
3. CIt provides a different pathway with a lower activation energy
4. DIt makes the reaction more exothermic

Raising the temperature by 10 °C can roughly double the rate of many reactions. What is the main reason?

1. AThe reaction becomes more exothermic
2. BThe activation energy itself is lowered by the extra heat
3. CThe particles become larger and easier to hit
4. DMany more collisions have at least the activation energy

ข้อใดต่อไปนี้เป็นกรดอ่อน

1. Aกรดไฮโดรคลอริก
2. Bกรดไนตริก
3. Cกรดแอซีติก (ในน้ำส้มสายชู)
4. Dกรดซัลฟิวริก