ใบงาน เคมีสำหรับข้อสอบเข้าพยาบาล พร้อมเฉลย

According to the Arrhenius definition, what does a base produce in water?

1. ACarbonate ions (CO₃²⁻)
2. BChloride ions (Cl⁻)
3. CHydroxide ions (OH⁻)
4. DHydrogen ions (H⁺)

What does the octet rule state?

1. AAtoms tend to gain, lose or share electrons to get 8 outer electrons
2. BEvery stable atom has exactly 8 protons in its nucleus
3. CAn atom can form a maximum of 8 covalent bonds
4. DEvery stable molecule contains exactly 8 atoms

Which element exists naturally as diatomic molecules (two atoms joined together)?

1. AIron
2. BHelium
3. COxygen
4. DSodium

A gas mixture contains nitrogen at 600 mmHg, oxygen at 150 mmHg and other gases at 10 mmHg. What is the total pressure?

1. A600 mmHg
2. B253 mmHg
3. C750 mmHg
4. D760 mmHg

On an energy diagram, the products are at a lower energy than the reactants. What kind of reaction is shown?

1. AExothermic
2. BNuclear
3. CEndothermic
4. DReversible only

คาร์บอนไดออกไซด์ 88 g (มวลโมลาร์ 44 g/mol) มีกี่โมล

1. A44 mol
2. B0.5 mol
3. C3872 mol
4. D2 mol

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. B300 mol
3. C0.5 mol
4. D2 mol

Why does atomic radius decrease from left to right across a period?

1. AThe atoms lose electrons across the period
2. BMore protons pull the electrons of the same outer shell closer
3. CEach element adds a new electron shell
4. DNeutrons push the electrons outward less strongly