Combined Science Double Award - 9204 OxfordAQA

Kinetic Theory

Gbogbo ọrọ náà

Stand a pan of crushed ice on a hot ring with a thermometer in it and watch the reading. It climbs to zero and then it stops. The ring is still glowing, the ice is visibly turning to water, joules are pouring in at hundreds every second, and the number on the thermometer refuses to move. It stays there for minutes. Only when the last sliver of ice has gone does the reading start to rise again, and later, at one hundred, it stalls a second time and stays stalled while the pan boils dry. Two flat stretches in one heating, and in both of them energy is arriving with nothing to show for it on the scale.

Nothing has gone missing. This lesson shows you where those joules went, and it hands you a way of reading any temperature against time graph as a story about particles: how far apart they are, how fast they move, and how tightly they are held to one another. You will compare the three states in one model, define specific heat capacity and put numbers into the equation that goes with it, learn why an impurity shifts a melting point, and finish by designing a cooling investigation of your own. One part of the topic belongs to the Extension Tier alone and is marked as such where it appears, so you will always know which paragraphs your own paper can ask you about.

Ebumnobi

  1. Kinetic theory can be used to explain the different states of matter and their properties. The particles in solids, liquids and gases have different amounts of energy. Students should be able to recognise, use and compare simple diagrams to represent key features of solids, liquids and gases.
  2. The specific heat capacity of a substance is the amount of energy required to change the temperature of one kilogram of the substance by one degree Celsius. The relationship between energy, E, mass, m, specific heat capacity, c, and temperature change, ∆θ, is:
  3. The specific latent heat of vaporisation of a substance is the amount of energy required to change the state of one kilogram of the substance from a liquid to a vapour with no change in temperature. The relationship between energy, E, mass, m, and specific latent heat of vaporization, LV , is:
  4. The specific latent heat of fusion of a substance is the amount of energy required to change the state of one kilogram of the substance from a solid to a liquid with no change in temperature. The relationship between energy, E, mass, m, and specific latent heat of fusion, LF , is:
  5. The melting point of a solid and the boiling point of a liquid are affected by impurities. Throughout Section 3.19, students should be able to explain the shape of the temperature-time graph for a substance that is either cooled or heated through changes in state.

Maapụ uche

E seela isiokwu a ka ị hụ otu echiche si ejikọta.

Mepee maapụ uche na ngwa

Akwụkwọ Ọmụmụ

A kilogram of ice at zero degrees and a kilogram of water at zero degrees are at exactly the same temperature, and yet they are not in the same condition at all. Getting from one to the other costs about 334 000 joules, which is roughly the energy a one bar electric fire delivers in five and a half minutes, and every last joule of it is spent without the thermometer moving by a hundredth of a degree. That is not a fault in the thermometer. Temperature only reports one thing about the particles, and during a melt that one thing is the only thing not changing.

Ndetu Nkuzi Zuru Ezu di na Ngwa Green Bridge

Nweta ngwa Green Bridge CBT na ekwenti gi ma o bu kompiuta maka ulo akwukwo IGCSE zuru oke: akwukwo ule ndi gara aga, usoro nyocha, eserese uche, kaadi omumu na nkuzi olu.

Akwụkwọ ndụmọdụ zuru oke nwere eserese
Onye inyeaka mmụta AI
Ule nnwale nwere oge a na-ahazi ozugbo i mechara
Ọ dị na Android, Windows, macOS, na Linux Ngwa iOS na-abia n'oge na-adighi anya

Nnyocha Ọmụmụ

Ekele diri gi maka imecha ihe karịrị na Kinetic Theory. Ugbu a na ị na-enyochakwa isi echiche na echiche ndị dị mkpa, ọ bụ oge iji nwalee ihe ị ma. Ngwa a na-enye ụdị ajụjụ ọmụmụ dị iche iche emebere iji kwado nghọta gị wee nyere gị aka ịmata otú ị ghọtara ihe ndị a kụziri.

Ị ga-ahụ ngwakọta nke ụdị ajụjụ dị iche iche, gụnyere ajụjụ chọrọ ịhọrọ otu n’ime ọtụtụ azịza, ajụjụ chọrọ mkpirisi azịza, na ajụjụ ede ede. A na-arụpụta ajụjụ ọ bụla nke ọma iji nwalee akụkụ dị iche iche nke ihe ọmụma gị na nkà nke ịtụgharị uche.

Jiri akụkụ a nke nyocha ka ohere iji kụziere ihe ị matara banyere isiokwu ahụ ma chọpụta ebe ọ bụla ị nwere ike ịchọ ọmụmụ ihe ọzọ. Ekwela ka nsogbu ọ bụla ị na-eche ihu mee ka ị daa mba; kama, lee ha anya dị ka ohere maka ịzụlite onwe gị na imeziwanye.

  1. Which statement describes the particles in a liquid? A. Held in fixed positions in a regular arrangement B. In contact with one another but free to slide past each other C. Widely separated and moving quickly in random directions D. Widely separated and held in fixed positions Answer: B
  2. What is the unit of specific heat capacity? A. J B. J/kg C. J/kg degC D. degC/J Answer: C
  3. The specific heat capacity of water is 4200 J/kg degC. How much energy is needed to raise the temperature of 2.0 kg of water from 15 degC to 35 degC? A. 42 000 J B. 84 000 J C. 168 000 J D. 294 000 J Answer: C
  4. A pure substance is heated steadily and its temperature stays constant for several minutes. Which statement is correct for that period? A. No energy is being transferred to the substance B. The energy transferred is increasing the average speed of the particles C. The energy transferred is separating the particles as the substance changes state D. The energy transferred is being destroyed Answer: C
  5. A salt is dissolved in a sample of pure water. What happens to the melting point and the boiling point of the sample? A. Both are raised B. Both are lowered C. The melting point is lowered and the boiling point is raised D. The melting point is raised and the boiling point is lowered Answer: C

Rue ajuju ndi a n'ime ngwa ahu

Rue ajuju ndi a n'ime ngwa ahu

Meecha Ajụjụ Ule Ọmarịcha

Ị chọrọ ime ajụjụ ule ọmarịcha gbasara Kinetic Theory? Budata ngwa Green Bridge CBT iji nweta ajụjụ ule ọmarịcha na nyocha zuru ezu gbasara isiokwu a.

Budata Ngwa Ahụ Na Google Playstore

Ihe nile ichoro iji nwee ihe ịga nke ọma na JAMB, WAEC & NECO.

Green Bridge CBT Mobile App
Onye Enyemaka Nkata AI Nke Ọmụmụ Ihe Ahaziri Maka Gị
Ajụjụ ule IGCSE, JAMB, WAEC na NECO karịrị 200,000
Ihe karịrị 1200 Nkọwa Nkuzi
Nkwado Na-enweghị Ịntanetị - Mụọ Ihe Mgbe Ọ Bụla, Ebe Ọ Bụla
Jadawalin Gada Kore
Akọkọ akọle iwe & Ibeere agbara
Sọfụma Ọrụ Gi & Ọganihu Gi
Nkọwa Miri Emi Maka Ọmụmụ Ihe Zuru Ezu