{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

CHEM LAB 39.docx

CHEM LAB 39.docx - Chem Lab 111113 How Dense is an Egg...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chem Lab 111113 9/14/2016 How Dense is an Egg? Objectve: - Determine the densiTes of eggs with varying degrees of freshness. Learn how to use a balance and 4 types of volumetric glassware. InTroducton: - An egg’s ability to Foat in saltwater has to do with its degree of freshness - If in an egg just Foats in a salt soluTon, the soluTon has the same density as the egg o Density is a characterisTc property of ma±er that can be used to idenTfy a substance De²ned as mass per unit volume or g/mL - A solid will sink in a liquid that’s denser, will Foat if the liquid is less dense, will just Foat if the liquid has the same density ±he ExperimenT What is the density of an egg? 1. Prepare a salt soluTon where an egg just Foats a. Obtain the mass and volume measurements of said soluTon i. Use a balance for mass (m), and mulTple devices for volume (v) b. Calculate the density of the soluTon (and egg) using m & v measurements c. Compare the density of a new egg to an old one. 2. Measurements: Learn how to measure m and v using equipment a. QuanTtaTve operaTons: i. PrioriTze precision: how close 2+ measurements, of the same quanTty, agree with each other 1. Random errors (unpredictable variaTons) are shown in the precision of data 2. ³o evaluate precision, repeat experiment several Tmes, with varying amounts of substances, while performing other operaTons the same, then check reproducibility of said experiment ii. PrioriTze accuracy: how much a measurement agrees with a known value 1. SystemaTc errors, typically from poor equipment or technique, causes inaccurate data iii. Precision is not the same as accuracy 3. Measuring devices are imperfect and uncertain
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
4. SigniFcant Fgures are needed ²or properly reporTng data
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}