Presentation on theme: "CHEMICALS AND CHEMICAL CHANGE"— Presentation transcript:
1 CHEMICALS AND CHEMICAL CHANGE Chapter 5.1BLM 5.1a, 5.1b
2 Chemicals and chemical Change CHEMISTRY – is the study of matter, its changes and its propertiesMATTER – is anything that has mass and takes up spaceATOM – the smallest particle of matter
3 PHYSICAL CHANGE – a change in a substance which does not produce a new substance. Easy to reverseEx. Melting iceCHEMICAL CHANGE – a change in a substance which does produce a new substance.Difficult to reverseEx. Match burning
6 Classify each substance as 1) A pure substance or a mixture, and 2) An element, molecule, heterogeneous mixture or homogeneous: a) Glass of milk b) Spoonful of sugar c) A bar of gold d) Orange juice with pulp
7 Science 10 – Nov. 3rdClassify each reaction as a physical or chemical reaction: a) Butter melting b) Cheese molding c) Breaking a chocolate bar in half d) Burning toast
8 Science 10 – Nov. 3rdClassify each substance as 1) A pure substance or a mixture, and 2) An element, molecule, heterogeneous mixture or homogeneous: a) Glass of milk b) Spoonful of sugar c) A bar of gold d) Orange juice with pulp
9 Physical Reaction vs. Chemical Reaction Physical reactions are easy to reverse while chemical reactions are not.Ex “When ice melts is it easy to reverse that reaction? Burning a match?”
10 Physical Trait vs. Chemical Trait Physical traits are either simple observations or things having to do with physical reactions.Color, smell, size, mass, boiling point, melting point.Chemical traits have to do with chemical reactions.Will it catch on fire?Ability to react with other chemicals.Stable or unstable.
11 Science 10 – Nov. 1st1) Classify each as 1) Pure substance or mixture, then 2) Element, compound, homogeneous mixture or heterogeneous mixture.SugarCopper wireAirOrange juice w/ pulpOrange juice w/o pulp
12 Science 10 – Nov. 1st2) Classify each as a physical change or a chemical change:Food rottingBreaking a carrot in halfWater boilingMaking toastDissolving salt into water
13 Science 10 – Nov. 1st3) Classify each as a physical trait or chemical trait:Water freezes at 0oCEthanol is a clear liquidGold does not react with acidAluminum is a malleable metalMercury metal is a liquid at room temperature
14 HOMEWORK QUESTIONS Page 175 QUESTIONS: #1,2,4,5,6,7 Explain in your own words the difference between element, atom, molecule and compound.Work on project
15 SOLUTIONS TO HOMEWORK QUESTIONS Q1 – classify each of the following as a pure substance or a mixtureA) soapy waterMIXTUREB) hydrogen gasPURE SUBSTANCEC) sodium chloride
16 QUESTION 2 Classify each of the following as an element or a compound. A) hydrogenELEMENTB) potassium carbonateCOMPOUNDC) waterD) Mg
17 QUESTION 4Classify each of the following as a physical property or a chemical property.A) Gasoline is a clear pink solutionPHYSICAL PROPERTYB) Gasoline burns in airCHEMICAL PROPERTYC) Water boils at 1000C.D) electric current can split water into hydrogen and oxygen gases
18 QUESTION 5When aluminum metal is added to hydrobromic acid, hydrogen gas and an aluminum bromide solution are formed.A) What kind of change has occurred?A chemical change has occurred because new substances were made.
19 QUESTION 5When aluminum metal is added to hydrobromic acid, hydrogen gas and an aluminum bromide solution are formedB) Which substances are the reactants and which are the products?Reactants – Aluminum and AcidProducts – Hydrogen + Aluminum Bromide
20 QUESTION 6Describe the chemical tests that can be used to identify the following gases.A) hydrogena flaming wooden splint causes a “pop”B) Oxygena glowing wooden splint relights (bursts into flame)
21 QUESTION 6 C) Carbon Dioxide A burning wooden splint extinguishes, OR when the gas is bubbled through limewater, the limewater changes from a clear, colourless solution to a cloudy white liquid (a precipitate is formed)
22 QUESTION 6 d) Water Vapour Changes the colour of cobalt chloride test paper from blue to pink
23 QUESTION 7When sodium carbonate is added to water, the sodium carbonate dissolves. When hydrochloric acid is added to the solution, the solution fizzes. What kinds of changes have occurred?
24 QUESTION 7 - ANSWERWhen sodium carbonate dissolves in water it is a physical changeA chemical change happens when gas is formed after hydrochloric acid is added ( fizz / Bubbles )