Test Review 1A (2014-2015)

Test Review 1A (2014-2015) The Practice of Chemistry

Lab Equipment Goggles Flask

What is this? Beakers

Flask

Test tubes

Pippette Crucible Tongs

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

A_____________observation is one that can be made without measurement Qualitative

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 10.0 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 16.3 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

Dimensional analysis • How many eggs are in 4 dozen • 4dozen x 12eggs/1 dozen = 48 eggs

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 2.50 g/cm3 X 100 = 20%

=3.50% 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

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. 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? 300g -160g= 140g m 140 g/75 ml= D V 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 • Tungsten W

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 ______ 0 100

273K • 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

Test Review 1A (2014-2015)