Hyde: SCH3U1 Name: Mark: /64 Math Matters Quiz 1. Match the following quantities with their correct units of measurement or definition. (7 marks) Letter Quantity Unit/Definition Density A. The amount of matter in an object – base unit of grams (g) Energy B. The distance between two points – base unit of metre (m) C. The hotness or coldness of an object – measured in Kelvin (K) or degrees Celsius (°C) D. The amount of space an object occupies – solids measured in cubic metres (m3), liquids measured in litres (L) Length Mass Mole E. The amount of a substance – measured in mol F. The mass per unit of volume of a substance – measured in kg/m3 or g/cm3 G. The capacity to do work (to move matter) – measured in joules (J) Temperature Volume 2. For each of the following diagrams, label the accuracy as either high or low. (8 × 0.5 = 4 marks) Accuracy: Accuracy: Accuracy: Accuracy: Precision: Precision: Precision: Precision: 3. The following measurements were made to determine the density of a material whose value was, according to the Handbook of Chemistry, 7.86 g/cm3. Trial One = 7.89 g/cm3 Trial Two = 7.87 g/cm3 Trial Three = 7.88 g/cm3 (Questions on next page.) a) Make a general statement about the accuracy of the trial results. (1 mark) b) Make a general statement about the precision of the trial results. (1 mark) c) Use the average of the three trials as the “measured value” and determine the numerical value for percent error. (3 marks) 𝑷𝒆𝒓𝒄𝒆𝒏𝒕 𝒆𝒓𝒓𝒐𝒓 = 𝑴𝒆𝒂𝒔𝒖𝒓𝒆𝒅 𝑽𝒂𝒍𝒖𝒆 − 𝑨𝒄𝒄𝒆𝒑𝒕𝒆𝒅 𝑽𝒂𝒍𝒖𝒆 × 𝟏𝟎𝟎% 𝑨𝒄𝒄𝒆𝒑𝒕𝒆𝒅 𝑽𝒂𝒍𝒖𝒆 d) Determine the percent difference between Trial One and Trial Two. (3 marks) 𝑷𝒆𝒓𝒄𝒆𝒏𝒕 𝑫𝒊𝒇𝒇𝒆𝒓𝒆𝒏𝒄𝒆 = 𝑫𝒊𝒇𝒇𝒆𝒓𝒆𝒏𝒄𝒆 𝒃𝒆𝒕𝒘𝒆𝒆𝒏 𝒕𝒘𝒐 𝒗𝒂𝒍𝒖𝒆𝒔 × 𝟏𝟎𝟎% 𝑨𝒗𝒆𝒓𝒂𝒈𝒆 𝒐𝒇 𝒕𝒘𝒐 𝒗𝒂𝒍𝒖𝒆𝒔 4. Measure the lengths of the following objects, making sure to include the estimated uncertainty in your measurement. (2 marks) Metric Ruler A: Metric Ruler B: 5. You are trying to measure the height of your friend, Bob. You have him stand up against a wall, and mark his height on the wall with a pencil. You only have a 30-cm ruler at your disposal with which to measure his height. Why would using a 30-cm ruler give greater uncertainty than using a metre stick? (3 marks) 6. Determine the number of significant digits for the following values. (6 marks) a) 35.006 b) 410 c) 675.00 d) 1.56 × 1020 e) 50 cats f) 0.000 00630 7. Express the following in scientific notation. (4 marks) a) 675 987 b) 0.000 006 57 c) 1300 d) 0.002 00 8. Round the following to three (3) significant digits. (5 marks) a) 543.56 b) 678 448 c) 0.006 95 d) 1445 e) 9 433 764 9. Complete the following calculations, making sure to round your final answer to the correct number of significant digits. Use scientific notation wherever appropriate. (8 marks) a. 9.745 km – 4.2 km b. 8.33 L + 0.4 L + 56.358 L c. 580.62 mm × (1.02 mm ÷ 0.7 mm) d. 3.72 × 103 6.5 × 107 10. Carry out the following unit conversions, using the conversion factors provided in the chart. a. 145 lbs to kg (2 marks) b. 6 pint to mL (4 marks) c. The speed of a light in a diamond is, 1.24 × 108 m/s. Convert this speed into km/day. (5 marks) d. The number of water molecules in 250.00 g of water, given that there are 6.022×10 23 molecules/g of water. (2 marks) e. The mass of a 10 m3 of gold, given that the density of gold is 19.32 g/mL. (4 marks)