ใบงาน เคมีสำหรับข้อสอบเข้าพยาบาล พร้อมเฉลย

สถานะใดของสสารที่อนุภาคมีรูปร่างและปริมาตรคงที่

1. Aของเหลว
2. Bพลาสมา
3. Cของแข็ง
4. Dแก๊ส

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

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

About what percentage of dry air is oxygen?

1. A50%
2. B1%
3. C78%
4. D21%

What is carbon-14 dating used for?

1. AFinding the exact age of rocks that are billions of years old
2. BDetecting carbon monoxide in a room
3. CMeasuring body temperature
4. DEstimating the age of material that was once alive

What are London dispersion forces?

1. AForces that hold protons together in the nucleus
2. BStrong bonds formed by transferring electrons
3. CAttractions between a hydrogen atom and a metal ion
4. DWeak, temporary attractions caused by shifting electrons in molecules

Why does the vapour pressure of a liquid increase as it is heated?

1. AThe attractions between the molecules become stronger
2. BMore molecules have enough energy to escape into the gas phase
3. CThe liquid's volume decreases and squeezes out vapour
4. DThe molecules become heavier and press harder on the surface

In terms of bonds, why is a reaction exothermic?

1. AMore energy is released forming new bonds than is absorbed breaking old ones
2. BMore energy is absorbed breaking old bonds than is released forming new ones
3. CForming bonds always absorbs energy
4. DNo bonds are broken in exothermic reactions

What is (8 × 10⁶) ÷ (2 × 10⁻²)?

1. A16 × 10⁴
2. B4 × 10⁴
3. C4 × 10⁸
4. D4 × 10⁻¹²