Change+of+state

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=Change of State=
 * 5.9 recall that particles in a liquid have a random motion within a close-packed irregular structure**
 * 5.10 recall that particles in a solid vibrate about fixed positions within a close-packed regular structure.**

Boiling is a phase transition from the liquid phase to gas phase that occurs at or above the boiling temperature. Evaporation usually occurs on the surface. Particles in liquid become the gas phase by gaining energy from the surroundings.
 * [[image:Picture_3.png width="565" height="312"]] ||
 * 5.8 understand that a substance can change state from liquid to gas by the process of evaporation or boiling**
 * Evaporation || Boiling ||
 * A process in which a substance changes its state from the liquid state to the gaseous state || A process in which a substance changes its state from the liquid state to the gaseous state without boiling ||
 * A process in which a substance changes its state from the liquid state to the gaseous state || A process in which a substance changes its state from the liquid state to the gaseous state without boiling ||


 * 5.7 understand that a substance can change state from solid to liquid by the process of melting**

Starter: States of matter Venn from echalk.co.uk

**Draw a particle diagram showing changes of state of Solid Liquid and Gas using triangle arrows**



 * Heat and temperature**

Heat or thermal energy is a type of energy (Joules, J) Temperature is a measure of how hot/cold something is (Celsius, °C) Not any colder than that temperature you can make || -273°C || 0K || = = Grade 7 Ruby Homework by Thursday 29th Nov. 2012
 * Status || Celsius(°C) || Kelvin(K) ||  ||
 * Boiling point of water || 100 °C || 373K ||
 * room temperature || 20 °C || 293K ||
 * Freezing/Melting point of water || 0°C || 273K ||
 * Absolute zero (No movement);

**Melting Ice, Boiling Water**
What is your independent variable? What is your dependent variable? What is your controlled variable? What change of temperature will you expect when boiling water? What change of temperature will you expect while melting ice?
 * Aim:** To investigate the change of state of water as the temperature increases.
 * Diagram:**

1.Prepare ice water in a 100ml beaker. 2. Measure the temperature of water every minute before heating it for 5 minutes. 3. Make a gentle flame but still blue, not orange then apply heat to water in the beaker. 4. Record the temperature of water every minute until water boils and keep measuring the temperature until the temperature stays about the same for 3 times in a row. 5. Plot the graph using your data collection.
 * Method:**

Graph: Plot a graph with the results you recorded and add a line of best fit.
 * Results:**
 * Time (min) || 0 || 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 11 || 12 || 13 || 14 || 15 || 16 || 17 || 18 || 19 || 20 ||
 * Temperature ( °C) || 0 ||  ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||
 * Temperature(Kelvin) ||  ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||   ||

Water changes its state from liquid to gas(steam) by __ boiling __ as the temperature goes up. Steam also changes state to water by the process called __c ondensation __ and water goes back to the state of ice by __ freezin __ g as the temperature decreases. The flat line on your graph shows where __ energy __ is being used to break __ bonds __ – this has to be done during __ melting/boiling __.
 * Conclusion:**

Why does the temperature __ stay __ at 0 degree Celsius when ice is melting? Explain your answer using the word energy.

Solids, liquids and gases from echalk.co.uk Fun facts of [|the Chemistry of Water] from youtube.com [|Why does ice float in water] from TED-ED youtube.com