CHM108 Lab Midterm Review
Calculate the volume, in cubic centimeters, of a box which is 125 cm long, 37 cm wide, and 68 cm high. Report the answer with correct significant figures in cubic centimeters.
310000 cm3
Words to describe physical changes.
Odor, hardness, texture, solubility, etc.
Insoluable
When a solid does not dissolve when added to a liquid
Soluble
When a solid is added to and dissolves in a liquid
Remove clothing and continue flushing the area for
15 minutes
The temperature of a room is 22.5 °C. What is this temperature expressed in Kelvin (K)?
295.65 K
Calculate the volume (in cm3) of a rectangular solid with the given dimensions, rounding your answer to the proper number of significant figures. 0.982 cm x 4.71 cm x 8.3 cm=
38 cm3
What is the correct reading of the volume in the pictured buret?
39.95 mL
What is the correct reading for the graduated cylinder in the close-up?
40.5 mL
Perform the calculation, rounding your answer to the proper number of significant figures. 91.2753 g - 42.367 g=
48.908 g
Which device is best for measuring the mass of a liquid?
A balance
Identify the common indicators that a chemical reaction has occurred.
A change in temperature, change in color, precipitation being formed, bubbles being produced
What is an MSDS?
A list of hazardous ingredients of a product, the physical and chemical characteristics, its effect on human health, etc. (Material Safety Data Sheet)
Explain the greenhouse gas effect.
A natural atmospheric warming in which solar energy is absorbed by the earth's surface and is reradiated and absorbed by certain atmospheric gases (primarily carbon dioxide and water vapor); absorb thermal infrared radiation
When should lab participants look at the Safety Data Sheet (SDS) of a substance?
Before using the substance
A precipitate is formed from two solutions.
Chemical
A solution heats up upon mixing with another.
Chemical
Bubbles are produced upon mixing two solutions.
Chemical
The color of a substance changes over time.
Chemical
What do NFPA 704 symbols tell you?
Color-coded safety system where blue=health hazard, red=flammability hazard, yellow=reactivity hazard
Gamma rays and visible light are both
Electromagnetic radiation
Density is an extensive property because it only depends on the object's size.
False
The density of an object with an irregular shape is impossible to measure.
False
Words to describe chemical changes.
Flammability, rusting, precipitate, color change, etc.
What depicted situations are considered safety violations?
Improperly worn eye protection, food and drink in the lab space
How is density measured?
Mass/Volume
Choose the most appropriate task for each pictured piece of glassware.
Measuring out a volume of liquid
A liquid freezes into a solid.
Physical
A solid dissolves into water.
Physical
Stand under the shower and
Pull the lever
What should you do every time before you leave the lab?
Remove your lab coat, if you are wearing one, remove your gloves, and wash your hands
Discrete light sources
Show only bright or dark lines at very distinct and sharply-defined colors
Move to the safety shower if you spill hazardous chemicals on your
Skin or clothing
Identify the potential uses for an iron ring.
Supporting a beaker on a piece of wire mesh, suspending a funnel, holding a crucible placed in a clay triangle
What is the relationship between energy and wavelength?
The longer the wavelength- the less energy (and vice versa)
What result could indicate either a chemical or physical change?
The state of matter of the material is altered
Sublimation
The transition of a substance directly from a solid state to a gas state
An object with a density less than 1 g/mL will float on water.
True
As wavelength increases, the amount of energy decreases
True
Density is a physical property of an object.
True
Density is an intensive property because it only depends on the object's identity.
True
Immiscible
Two distinct layers will form when poured together
Continuous light sources
When light is composed of a wide, continuous range of colors
Miscible
When two liquids are mixed and become a uniform mixture
The color with the highest energy in the visible spectrum is
blue
The color with the lowest energy in the visible spectrum is
red
