ใบงาน เคมีสำหรับข้อสอบเข้าพยาบาล พร้อมเฉลย

What is the smallest particle of an element that still has the chemical properties of that element?

1. AA proton
2. BA nucleus
3. CAn atom
4. DAn electron

What is an empirical formula?

1. AThe simplest whole-number ratio of atoms in a compound
2. BA drawing of how the atoms are bonded
3. CThe mass of one mole of a compound
4. DThe actual number of each atom in one molecule

In a chemical reaction, what is the limiting reactant?

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

อุณหภูมิของน้ำแข็งในน้ำจะเป็นอย่างไรขณะที่น้ำแข็งกำลังละลาย

1. Aคงอยู่ที่ 0 °C จนกว่าน้ำแข็งจะละลายหมด
2. Bเพิ่มขึ้นอย่างสม่ำเสมอตลอดเวลา
3. Cเพิ่มขึ้นถึง 100 °C ทันที
4. Dลดลงต่ำกว่า 0 °C

มวลโมลาร์ของน้ำคือเท่าใด (H = 1 g/mol, O = 16 g/mol)

1. A10 g/mol
2. B18 g/mol
3. C17 g/mol
4. D32 g/mol

What is the molar mass of sodium chloride, NaCl (Na = 23, Cl = 35.5 g/mol)?

1. A81.5 g/mol
2. B12.5 g/mol
3. C58.5 g/mol
4. D23 g/mol

Why does a burn from steam at 100 °C usually cause more damage than one from liquid water at 100 °C?

1. ASteam particles are hotter than water particles at the same reading
2. BSteam releases a large amount of extra energy as it condenses on the skin
3. CLiquid water cannot pass any of its heat to the skin
4. DSteam carries dissolved acid that damages the skin

Ethanol (CH₃CH₂OH) and dimethyl ether (CH₃OCH₃) have the same formula, C₂H₆O, but ethanol boils at a much higher temperature. Why?

1. AEthanol has an O–H group, so its molecules form hydrogen bonds with each other
2. BEthanol has more carbon atoms
3. CEthanol molecules are heavier than dimethyl ether molecules
4. DDimethyl ether is ionic and ethanol is covalent