The Practice of Chemistry Test Review 1A (2014-2015) The Practice of Chemistry
Lab Equipment Goggles Flask
What is this? Beakers
Flask
Test tubes
Crucible Tongs Pippette
A D B E C Flask Graduated Cylinder Test Tube Beaker Test tube rack Name the following A D Flask Graduated Cylinder B E Test Tube Beaker C Test tube rack
What is the The Order of the steps of the scientific method Observation Hypothesis Experiment Data collection Conclusion
Density A bottle contains 100 mL of a liquid. The total mass of the bottle and the liquid together is 250 g. The mass of the empty bottle is 50 g. What is the density of the liquid? Formula d=m/v 200g /100 mL=2.0 g/mL
Density What is the mass of a 100 milliliter sample of water? Remember the density of water is 1 g/cm3 100grams
Density A sample has a mass of 50 grams and a volume of 25 cm3. What is the density? 50 g /25 cm3 = 2 g/cm3 The same sample is cut in half. It has a mass of 25 grams and a volume of 12.5 cm3. What is the density? 25 g /12.5 cm3 = 2 g/cm3
Qualitative A _____________observation is one that can be made without measurement
Quantitative A ____________ observation is one that uses measurement
Chemistry and Matter: Basic Concepts Identify each of the following as either a qualitative or quantitative observation. A. The density of water is 1.0 g/mL Quantitative B. An base has a bitter taste Qualitative
Chemistry and Matter: Basic Concepts Identify each of the following as either a qualitative or quantitative observation. A. The mass of the rock is 25 grams. Quantitative B. A leaf has a green color. Qualitative
Metric conversion Convert 6000 mg to cg Convert 400 Liters to mL Convert 2.5 m to km K H Dk base d c m 600 cg 400000 mL 0.0025 km
A vessel contains 85 mL of water. A sample of 10 A vessel contains 85 mL of water. A sample of 10.0 g of copper metal is dropped into this vessel, raising the level of water in it to 86.12 mL. What is the density of the copper sample? 86.12mL – 85mL=1.12mL 10g /1.12mL= 8.93g/mL
A cube of metal is 1. 42 centimeters on an edge. It has a mass of 16 A cube of metal is 1.42 centimeters on an edge. It has a mass of 16.3 grams. What is the density of this metal? 1.42 X 1.42 X 1.42=2.86 cm3 16.3 grams 2.86 cm3 =5.69 g/cm3
How many eggs are in 4 dozen Dimensional analysis How many eggs are in 4 dozen 4dozen x 12eggs/1 dozen = 48 eggs
Percent error = actual – experimental actual X100 Percent error Percent error is the ratio of an error to an accepted value. Percent error = actual – experimental actual X100
Calculate the percent error. The density of an object is 3.00 g/cm3. Does it sink or float? Sink because greater than 1.0 g/cm3 The accepted value of density is 2.50 g/cm3. Calculate the percent error. 3.00 g/cm3 - 2.50 g/cm3 X 100 =20% 2.50 g/cm3 0.5 g/cm3 X 100 = 20%
What is the percent error if a measured value is 24 What is the percent error if a measured value is 24.59 g/mL and the accepted value is 25.49 g/mL? 25.49-24.59= 0.9 X100 25.49 =3.50%
How many minutes are in 4 days Dimensional analysis How many minutes are in 4 days 4 days X 24 hours/1 day X 60 minutes/1 hour = 5,760 minutes
Lab safety
A bottle contains 75 mL of a liquid A bottle contains 75 mL of a liquid. The total mass of the bottle and the liquid together is 300 g. The mass of the empty bottle is 160 g. What is the density of the liquid? m D V 300g -160g= 140g 140 g/75 ml= 1.9g/mL
Weird 11
Element: What is the Symbol and name 47 Ag Silver
Element: What is the Symbol and name 26 Fe Iron
Element: What is the Symbol and name 51 Sb Antimony
Element: What is the Symbol and name 80 Hg Mercury
Element: What is the Symbol and name 79 Au Gold
Element: What is the Symbol and name 82 Pb Lead
Element: What is the Symbol and name 74 W Tungsten
Element: What is the Symbol and name 11 Na Sodium
Element: What is the Symbol and name 19 K Potassium
Element: What is the Symbol and name 29 Cu Copper
Element: What is the Symbol and name 50 Sn Tin
The freezing point in Celsius is ____ and the boiling point is ______ 100
On the Kelvin scale, water freezes at about _____ and boils at about ____ K. 373
Convert the following 297 24oC = _____K 12oC = _____K 214K = _____oC 200K = _____oC 285 -59 -73