1. 1st Nine Weeks Test Study Guide Answers

2. 1. Solubility – the ability of one material to dissolve in another material; can be used to separate solutions ex. Sugar/sand/water 2. Thermal conductors – material through which thermal energy flows easily ex. metals 3. Thermal insulators – material through which thermal energy flows slowly ex. Cloth; winter coat 4. Specific heat – amount of thermal energy needed to raise the temperature of 1kg of material 1 degrees Celsius

3. 5. Thermal expansion – an increase in a material’s volume when temperature is increased ex. Hot air balloon 6. Thermal contraction – a decrease in a material’s volume when temperature is decreased 7. Thermostat – a device that regulates temperature of a system 8. Bimetallic coil – used in a thermostat to regulate temperature; made of two types of metals that expand and contract at different rates

4. 9. Convection current – movement of fluids in a cycle because of convection 10. Heating appliance and examples – device that converts electric energy into thermal energy ex. Curling iron, toaster, oven 11. Conduction – transfer of thermal energy due to collisions between particles 12. Radiation – energy carried by electromagnetic waves ex. Sun rays

5. 13. Convection – circulation of particles within a material caused by differences in thermal energy and density 14. Heat – the movement of thermal energy from a region of higher temperature to a region of lower temperature 15. Thermal energy – sum of the kinetic and potential energy of the particles that make up an object 16. Kinetic energy – energy due to motion

6. 17. Potential energy – stored energy due to the interaction between two objects 18. Temperature – measure of the average kinetic energy of the particles in a material 19. Conductivity – the ability or power to conduct or transmit heat, electricity, or sound 20. Law of conservation of mass – mass is neither created nor destroyed. In a closed system, mass of reactants is equal to mass of products.

7. 21. How does heating occur? when thermal energy is transferred from a warmer object to a cooler object 22. How is energy transferred in a heat engine? chemical energy (gas) > thermal energy ( combustion) > mechanical energy (motor runs and car moves) 23. What is the formula for calculating volume? V = LWH 24. What is the difference between chemical and physical properties? chemical property – ability or inability of a substance to combine with or change into a new substance physical property – characteristic you can observe using your senses without changing the material

8. 25. What are signs of a chemical change
25. What are signs of a chemical change? color change, formation of a gas, smoke or precipitate, light, or heat 26. List examples of physical properties (and changes) Physical properties – color, mass, density, volume, solubility, melting/boiling point Physical changes – dissolving, changing size, shape, form or state 27. How does temperature effect the state of matter of water? As temperature increases, water changes from a solid > liquid > gas, it changes its state of the matter.

9. 28. List the steps of the design process in order.
Identify the Problem or need
Research the problem and brainstorm solutions
Design solutions
Construct a prototype
Test & Evaluate
Redesign
Communicate results
29. What is the difference between scientific theories and laws?
laws are always true
30. How does a refrigerator work?
coolant is used to move thermal energy from inside (cooler location) to the outside of the fridge (warmer location)