Honors Chemistry Measurement Worksheet 1.1 Name _________________________________ Date ____________ Class _____________ All work is to be completed in pencil. Show equations used, label all units. Express the following numbers in standard notation or in scientific notation Standard Notation Scientific Notation 1. 590,056.0 2. 0.00346 3. 100 4. 2.33 x 10-4 5. 1.2430 x 107 6. 9.3 x 100 Determine the number of significant digits in each of the following 1. .93 __________ 6. 1.008 _________ 11. 345, 288.00 __________ 2. 340 __________ 7. 10001 __________ 12. 1,250,250 __________ 3. 0.097 __________ 8. 600 13. 0.010012 __________ 4. 39.5 __________ 5. 0.00760 __________ 9. 1.95 x __________ 103 10. 541.005 __________ 14. 11.4 x __________ 15. 1 10-8 __________ __________ Complete the indicated operation and provide the final answer with the correct number of significant digits Problem Calculator answer 1. 2.698 x 33.20 x 1.5611 2. 8.032 0.591 3. (3.2 x 103) (4.21x 102) 4. 3 x 154 5. 3.00 x 154 6. 7.623 + 85.0 + 9.815 7. 230.72 + 0.00861 8. 10.96 - 5.5 9. 23.6 - 16.1218 Answer rounded to the correct # of Sig.Figs. 10. 2.5 + 2.34 + 3.6543 11. (12.01 + 1.01 + 6)/101.4 12. determine the average of the following numbers: 8.2, 4.2, 11.8, 10.01 Density calculations. Show all work. Always include units. Box final answer. Pay attention to sig. fig’s. 𝒅 = 𝒎𝒂𝒔𝒔 𝒗𝒐𝒍𝒖𝒎𝒆 1. A sample of seawater has a mass of 158 grams and has a volume of 156 mL. What is the density? 2. What is the mass of ethyl alcohol that fills a 200.0 mL container? The density of ethyl alcohol is 0.789 g/mL. 1 3. A block of lead has dimensions of 4.50 cm by 5.25 cm by 6.05 cm. The block has a mass of 1587 g. From this information calculate the density. 4. The hydrogen stored in a large weather balloon weighs 13.558 g. What is the volume of this balloon if the density of hydrogen is 0.089 g/mL? Dimensional Analysis: 16 oz = 1 lb 1oz = 28.35 g 1kg = 2.2 lbs 1 L = 1.06 qts 1 in = 2.54 cm 1 ft = 12 in 1 mile = 1.61 km 1 mile = 1760 yds 2000lbs = 1 ton 1 cm3 = 1 mL 1 gallon = 4 qts 1mole=6.02 x 1023 15 birds = 1 dog 6 birds = 1 cat 4 birds = 1 frog 1. 3.61 lbs to kg 4. 4760 kg to tons 2. 0.43 oz to grams 5. 0.025 in to mm 3. 860.0 g to pounds (lbs) 6. 5.0 moles of C atoms to # of atoms Precision/Accuracy: Student A Student B Student C Trial 1 .192 g .222 g .010 g Trial 2 .204 g .212 g .009 g Trial 3 .174 g .223 g .011 g 1. Which student has data that is the most accurate (accepted value is 0.160 g), explain. Average 2. Which student has the best precision? Explain. 3. Which student has the best overall data? 2 Moles: 1. Calculate the mass in grams of each of the following: a) 2.0 moles of C b) 1.25 moles of O2 c) 0.05 moles of CO2 d) d) .25 mol of He 4.Make the following conversions: a) 55.5g of H2O to moles. b) .350 moles of sulfuric acid, H2SO4 to grams c) 6.63 x 1024 propane molecules C3H8 , to grams d) 1.50 x 1024 molecules of formaldehyde to grams. e) How many oxygens are represented in each of these formulas? i. Ca(OH)2 2.5 x 10-3 moles of benzene. Structural formula is shown here: 2.Calculate the molar mass of each of the following compounds: a) methanol, CH3OH b) sucrose, C12H22O11 c) 1-propanol, CH3CH2CH2OH d) calcium phosphate, Ca3(PO4)2 ii. Al2(SO4)3 iii. K2SO4· 3H2O 5. What is the percent composition of oxygen in formaldehyde? See structure above (4d) for the formula. 6. The compound dioxin, C12H4Cl4O2 , which has been linked to birth defects. What is the percent composition of all the elements in this compound? 3.Calculate the number of atoms or molecules of the following quantities: a) 20.0 g of Ca b) 3.34 mol of CO2 c) 68.0 g of H2S 3 Graduated Cylinder Worksheet A graduated cylinder can have numerous scales. 1) Determine the value for the minor grids on the cylinder. a) ______ b) _______ c) _______ d) _______ When reading a graduated cylinder you need to keep the graduated cylinder on the desk and lower your eyes to the level of the meniscus and you read where the bottom of the meniscus is. Be sure to include one point of estimation in your reading. 2) Determine the volume of the liquids in the following cylinders: a) _________ b) _________ c) _______ d) _________ 3) Draw in the meniscus for the following readings: a) 49.21 mL b) 18.2 mL c) 27.65 mL d) 63.8 mL 4