1. DO NOW What we measured in this lab What does this mean?Example A Volume of Air in the test tube at start The total volume in the test tube when the tube is completely filled up 78 mL B Volume of air in test tube after candle goes out After we put the test tube over the lit candle we measured how far the water came up. Then we filled it up with water to the line This represents the VOLUME OF NITROGEN 63 mL C Volume of oxygen This was how far the water came up in the test tub. We get this by subtracting A-B This represents the VOLUME OF OXYGEN 78-63= 15 mL Percentage of Oxygen in the air This is the volume of oxygen over the total volume C/A X 100 18/78 X 100= 19.2% % of oxygen in the air = volume of oxygen in test tube x 100 volume of air in test tube at start Data Table: A student obtained this data in his lab Volume of air in the test tube from the start = 75 ml Volume of air in the test tube after the candle goes out = 58 ml What is the volume of nitrogen- ______________ What is the total volume of air in the test tube? _______________ What is the percentage of oxygen in the test tube? __________________ What is the volume of oxygen in the test tube? __________________ Use the example in the chart at the top of the worksheet…… To complete the bottom of the worksheet……..

2. % of oxygen in the air = volume of oxygen in test tube x 100 volume of air in test tube at start Data Table: A student obtained this data in his lab Volume of air in the test tube from the start = 75 ml Volume of air in the test tube after the candle goes out = 58 ml What is the volume of nitrogen- ______________ What is the total volume of air in the test tube? _______________ What is the percentage of oxygen in the test tube? __________________ What is the volume of oxygen in the test tube? __________________ DO NOW What we measured in this lab What does this mean?Example A Volume of Air in the test tube at start The total volume in the test tube when the tube is completely filled up 78 mL B Volume of air in test tube after candle goes out After we put the test tube over the lit candle we measured how far the water came up. Then we filled it up with water to the line This represents the VOLUME OF NITROGEN 63 mL C Volume of oxygen This was how far the water came up in the test tub. We get this by subtracting A-B This represents the VOLUME OF OXYGEN 78-63= 15 mL Percentage of Oxygen in the air This is the volume of oxygen over the total volume C/A X 100 18/78 X 100= 19.2% Use the example in the chart at the top of the worksheet…… To complete the bottom of the worksheet……..

3. % of oxygen in the air = volume of oxygen in test tube x 100 volume of air in test tube at start Data Table: A student obtained this data in his lab Volume of air in the test tube from the start = 75 ml Volume of air in the test tube after the candle goes out = 58 ml What is the volume of nitrogen- ______________ What is the total volume of air in the test tube? _______________ What is the percentage of oxygen in the test tube? __________________ What is the volume of oxygen in the test tube? __________________ DO NOW What we measured in this lab What does this mean?Example A Volume of Air in the test tube at start The total volume in the test tube when the tube is completely filled up 78 mL B Volume of air in test tube after candle goes out After we put the test tube over the lit candle we measured how far the water came up. Then we filled it up with water to the line This represents the VOLUME OF NITROGEN 63 mL C Volume of oxygen This was how far the water came up in the test tub. We get this by subtracting A-B This represents the VOLUME OF OXYGEN 78-63= 15 mL Percentage of Oxygen in the air This is the volume of oxygen over the total volume C/A X 100 18/78 X 100= 19.2% Use the example in the chart at the top of the worksheet…… To complete the bottom of the worksheet…….. 75 mL 58mL

4. % of oxygen in the air = volume of oxygen in test tube x 100 volume of air in test tube at start Data Table: A student obtained this data in his lab Volume of air in the test tube from the start = 75 ml Volume of air in the test tube after the candle goes out = 58 ml What is the volume of nitrogen- ______________ What is the total volume of air in the test tube? _______________ What is the percentage of oxygen in the test tube? __________________ What is the volume of oxygen in the test tube? __________________ DO NOW What we measured in this lab What does this mean?Example A Volume of Air in the test tube at start The total volume in the test tube when the tube is completely filled up 75 mL B Volume of air in test tube after candle goes out After we put the test tube over the lit candle we measured how far the water came up. Then we filled it up with water to the line This represents the VOLUME OF NITROGEN 58mL C Volume of oxygen This was how far the water came up in the test tub. We get this by subtracting A-B This represents the VOLUME OF OXYGEN Percentage of Oxygen in the air This is the volume of oxygen over the total volume C/A X 100 Use the example in the chart at the top of the worksheet…… To complete the bottom of the worksheet…….. 75 mL 58mL 75 mL 75 mL – 58 mL = 17 mL 17 mL/75 mL x 100 = 22.7%