Lab 1, Post lab Questions, Measurements and Density

1. Which of the following samples may be weighed on an analytical balance without a container? A.glass beads B. dry sand C.paper clips D.sucrose E. all the above 2. Touching the sample container with bare hands without gloves affects the mass recording of an analytical balance due to moisture on the hands. A. true B. False

substances have a definite and unchanging chemical composition. Examples of substances are salt, water, baking soda, carbon dioxide and oxygen. They are substances because their composition is____.

Spotify Web Playe... M Common Ethical D... O CHEMICAL REACTIONS Using the Avogadro Number An aluminum atom has a mass of 4.48 × 10 -23 g and a small airplane has a mass of 5000. kg. Use this information to answer the questions below. Be sure your answers have the correct number of significant digits. What is the mass of 1 mole of aluminum atoms? How many moles of aluminum atoms have a mass equal to the mass of a small airplane? Explanation Check

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A student performed the same experiment as you. The following data was recorded in their lab notebook. Mass of Final buret volume, Mg, g Pbarometric, in Hg PH20, torr T, °C ml 0.037 37.52 28.62 17.5 20.0 Calculate the student's experimental value of R. Round your answer to four places after the decimal. 1.20 RE F6 FB F9 DID 8

O STOICHIOMETRY Using the Avogadro Number A penny has a mass of 2.50 g and the Moon has a mass of 7.35 x 10“ kg. 22 Use this information to answer the questions below. Be sure your answers have the correct number of significant digits. What is the mass of 1 mole of pennies? Round your answer to 3 significant digits. How many moles of pennies have a mass equal to the mass of the Moon? Round your answer to 3 significant digits. Explanation Check © 2021 McGraw-Hill Education. All Riahts Reserved. To átv

Spotify Web Playe.. M Common Ethical D... O CHEMICAL REACTIONS Using the Avogadro Number 22 A penny has a mass of 2.50 g and the Moon has a mass of 7.35 × 10*“ kg. Use this information to answer the questions below. Be sure your answers have the correct number of significant digits. What is the mass of 1 mole of pennies? Ox10 How many moles of pennies have a mass equal to the mass of the Moon? Explanation Check O 2022 McGraw Hill LLC. AlI Rights Re

A chemist measures the amount of nitrogen gas produced during an experiment. She finds that 27.7 g of nitrogen gas is produced. Calculate the number of moles of nitrogen gas produced. Round your answer to 3 significant digits. mol x10 Elanation Check O 2022 McGraw Hill LLC. All Rights Reserved. Terms of Use Privacy Center Accessiblity 80 F Cloudy DELL Delete PrtScr Insert F11 F12 F9 F10 F7 F8 F5 F6 F3 F4 F1 F2 Backspace

A 0.611 gram sample of copper is carried through the steps of this experiment. At the completion of the last step, 0.427 grams of copper are recovered. What is the percent recovery of the copper metal? Give your answer in in decimal format. When entering units, use proper abbreviated units with proper capitalization.________  ______Answer   Units

4) Activity 5: Check for Understanding (30 mins) A. True or False. Draw a check () mark in the given space if the statement is CORRECT and an (X) mark if the statement is INCORRECT. 1. Solid has a definite shape and indefinite volume. 2. BEC is a hot gas with negative and positive particles moving at a high speed. 3. Gas particles are moving randomly hence making it more expandable. 4. Oxygen is an example of a gas and at the same time element. 5. Malleability is an example of an extensive property. 6. Freezing water to become an ice is an example of physical change. 7. Cooking of egg is a physical change because it will only change its appearance. 8. Chemical change is usually irreversible. 9. Color alone is a physical property. But once a substance changes its color, it may indicate that it has undergone chemical change. 10. Volume is an intensive property.

Experiment 3: Determination of the Average Mass of a Penny  Number of pennies: 5 Mass of pennies (weighed together): 13.2 Mass of penny 1: 2.5 Mass of penny 2: 2.5 Mass of penny 3: 2.6 Mass of penny 4: 2.5 Mass of penny 5: 3.1 please help me with this part and show me all step  ??????? ???? ?? ? ?????=??? ?? ?ℎ? ?????????? ?????? ?? ?ℎ? ???? ???????/5  1. Total Mass of five pennies (weighed separately): 2. Average mass of a penny (using mass of five pennies weighed together)

Chemistry initial mass of benzoic acid 2g crude mass 1.45g

Based on the molecule below with each carbon labeled with sequential numbers, answer the following question: 1 H3C H 2 с H ₂ C. 4 3 CH3 5 ين H₂ C 6 H3C 8 7 C List the "Quaternary" carbon(s) found in the compound above: (please answer like this in sequential number order: #x, #y, etc...) 10 CH3 CH3 9

STPKsYapxmOBQpqJ9sYHEQf udwLFoPO2ojmMGw/edit s Help Last edit was seconds ago B U A G O O- E E E E E E - E - E E 14.5 3 4 5 6 You are asked to perform an experiment to determine the density of square block below. In order to complete your calculations you will need to (AKS 1b, DOK1). Question options: 1. Use the electronic balance to determine the mass of the block. 2. Use water displacement to determine the volume of the block. bD 1. Use the electronic balance to determine mass. 2. Use ruler to measure the length, width, and height to determine volume. C= 1. Use a pipet to determine the mass of the block. 2. Use water displacement to determine to volume of the block. Pr Au 立

A virus has a mass of 9.0 * 10 to the negative twelth and an oil tanker has a mass of 3.0 * 10 to the seventh kg Use this information to answer the questions below. Be sure your answers have the correct number of significant digits. 1.  What is the mass of 1 mole of viruses? g Round your answer to 2 significant digits.   2. How many moles of viruses have a mass equal to the mass of an oil tanker?   Round your answer to 2 significant digits.

Initial Water Volume: 12.70 mL Final Water Volume: 13.49 mL Mass of Solid: 7.11 g   Density of Solid: ________________ Identity of Irregular Solid: If copper’s d= 8.96 g/ml is it reasonable that the unknown is copper?

7 Calculate the mass (in g) of oxygen in a 76.9 g sample of Ni(BrO4)2 (MM = 346). Report your answer to 3 significant figures. Type your answer.... Previous

Part B Gather all of your pennies dated before 1982. Then follow the steps to complete the table. Include units as necessary. 1. Record the number of pennies dated before 1982. 2. Weigh (as a group) the pennies dated before 1982. Record the total mass. If you're unfamiliar with using an electronic balance, watch this video before continuing. 3. Calculate and record the average mass of a single penny. If you need help with the calculation, visit the averaging data section of the math review e. x' X, Font Sizes A A = E 至玉 田。 number of pennies combined mass of the pennies (g) average mass of a penny (g) Characters used: 82/15000

121 (OL) Lab 3 Den... V Layout Search References Mailings Review View Help 1 2 3 5 6 I i Lynette Maina Commer 7 LE T Chem 121(OL) Lab 3: Density of Common Materials Part C Thickness of Aluminum Foil (For help understanding the calculations read the introduction and procedure) An experiment performed for Part C to measure the length, width and mass of a piece of aluminum foil gave the following data. You will use this data to solve for the thickness of aluminum foil using the equation from Part C in the introduction. Length of foil Width of foil Mass of foil 13.10 cm 9.50 cm 9.745 g Use the data in the table to determine the thickness of your aluminum foil (in cm) using the 2.6989 g/mL for the density of aluminum then convert this value to meters (m) and micrometers (um). Show your work here (use back if necessary). ons: On Accessibility: Investigate F3 F4 W cm K F5 ►11 F6 K H m um DELL F7 F8 Gu F9 Focus BB 5= 57°F Mostly sunny 4/1 F10 F11 F12 PrtScr "T

Fill in the blanks by writing the name of the definition: _________ is a substance made up of only a single type of atom.     a. Element b.   mixture c. alloy d. Compound

2. What’s the main purpose of the glass shields on an analytical balance? A. To calibrate the balance B. To stop the current C. To keep out pests D. To prevent finger prints from getting on the weigh pan

=2591470&isprv3&drc%3D0&.gi=247580 How many grams of H2SO4 are present in 4.0*102 formula units of H2S04? Round your answer to 1 decimal place. Your Answer: Answer units D Add attachments to support your work Previous Page Next Page Page 1 of 6

Which statement is true?   Question 12 options:    Precision is measured by standard deviation.   Precision is measured by error or relative error.   Accuracy is measured by the standard deviation.

In question # 4, the mass of a 8.45 m3 piece of Cu is ___________g.  Do not report your answer in scientific notation

ome some City University o... Works - Kingsbo... both - Blackboard... tion-CLEARED4 Scientific Method? 7... # 2 6.02 QUESTION 7 One mole of particles of any substance contains how many particles? 3 × 10-10 particles 3 x 1010 particles 106 particles 6.02 x 10-23 particles 6.02 x 1023 particles Click Save and Submit to save and submit. Click Save All Answers to save all ans 3 16 MAR 23 245 átv 7 2

S [Review Topics] a. Merchants usually sell small nuts, washers, and bolts by weight (like jelly beans!) rather than by individually counting the items. Suppose a particular type of washer weighs 0.110 g on the average. What would 78 such washers weigh? g Submit Answer b. Merchants usually sell small nuts, washers, and bolts by weight (like jelly beans!) rather than by individually counting the items. Suppose a particular type of washer weighs 0.110 g on the average. How many washers would there be in 240. g of washers? washers Retry Entire Group Show Hint [References] 9 more group attempts remaining Previous Next> Save and Exit

The number of particles in 1 mole of hydrogen gas is __________. Express your answer using three significant figures.

3. A method of analysis yields masses of gold that are low by 0.4 mg. Calculate the percent relative error caused by this result if the mass of gold in the sample is a. 500 mg​​ b. 250 mg c. 60 mg 4. The method described above is to be used for the analysis of ores that assay about 1.2% gold. What minimum sample mass should be taken if the relative error resulting from a 0.4-mg loss is not to exceed a. -0.1% b. -0.8%

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+ An aqueous solution at 25 °C has a OH concentration of 1. x 10 M. Calculate the H,O' concentrat

6. Question: Hint: Chapter: 1 Lesson: 2 A student weighs 20 M&Ms and finds that the average weight of a single M&M is 0.8695 g. How many M&Ms are in a 1 lb (453.6 g) bag of M&Ms? Assume that all of the M&Ms have the average mass of a single M&M.