Chemistry Lab Final Exam Review
A chemical reaction is a rearrangement of the elements in the reactants.
True
A glass rod is used to decant a liquid.
True
A plot of of degrees Celsius versus the corresponding degrees Fahrenheit is a line
True
A pure substance can be an element or a compound.
True
A solution is a homogeneous mixture
True
A triple bond consists of six electrons.
True
Acids will attack any metal and produce hydrogen gas.
True
All nitrates are soluble.
True
All wood floats in water.
True
An oxidation/reduction reaction involves the transfer of protons.
True
Both water and H2S have a bent molecular shape.
True
Bubbles of air inside an object or clinging to its outside can make its density seem less than it would otherwise be.
True
Chalk and shells contain the same ingredient as an antacid.
True
Colligative properties depend only on the number of dissolved particles per L of solution
True
Compounds containing sodium ion, potassium ion, or lithium ion are always soluble.
True
Copper is an example of a variable charge ion.
True
Determining chemical properties involves changing the identity of the substance being tested.
True
Distillation separates substances based on differences in their boiling points.
True
For this experiment, the type of reaction that produced oxygen gas was a combustion.
True
Gold is a very unreactive metal.
True
Heavier objects tend to have greater densities.
True
If a color change occurs when two solutions are mixed, a chemical reaction has probably taken place.
True
If a liter of water contains two moles of dissolved particles, its boiling point will double
True
If several objects sitting in the sun have different specific heats, the one with the lowest number will have the highest temperature.
True
If the temperature of a substance increases, its atoms and molecules are moving faster.
True
In an exothermic reaction, the products have less energy than the reactants.
True
In ionic compounds, the amount of positive charge must equal the amount of negative charge.
True
In the reaction inside an activated cold pack, heat is one of the reactants.
True
In the specific heat experiment, it is important to obtain a careful measurement of the metal's weight.
True
Ionic compounds are held together by shared electrons.
True
Metal ores are mostly metal oxides.
True
Mixing MgSO4 solution with a Na2CO3 solution produces no reaction.
True
Molecular compounds are made up of all nonmetals.
True
Most sulfates are insoluble.
True
PbI2 is insoluble.
True
Phosphate is an example of a polyatomic ion.
True
Purification procedures have to remove both soluble and insoluble impurities.
True
Silicon dioxide is used to preserve the color and flavor of foods.
True
Sodium fluoride, sodium chloride, and sodium iodide all have similar purpose when used as an ingredient in products.
True
Some iron compounds have a red blood color.
True
The activity series places the most reactive metals at the top of the list
True
The activity series predicts that a metal cation higher on the list will react with a solid metal lower on the list.
True
The density of an object is determined by its composition.
True
The dissolving of a substance is a type of reaction.
True
The earth's tectonic plates are less dense than the mantle and core.
True
The filtrate is always waste material to be discarded
True
The first batteries utilized reactions of metals and metal ions.
True
The line spectra for fluorescent light has very distinct bands.
True
The particular color of a beam of light is due to wavelength.
True
VSEPR theory is used to predict the formula of a compound.
True
Volume displacement is a good way of measuring the volume of small or irregular objects
True
You should never put chemicals directly on the balance
True
Zinc oxide and titanium dioxide are effective sunscreens because they are so opaque.
True
Less than half of the elements we know are metals.
False; most elements are metals.
The desired type of flame on a Bunsen burner is yellow and luminous
False; transparent blue
A positive charged ion is called an anion.
False; Positive charge-cation negative charge-anion
Potassium gives a bright yellow flame test.
False; Potassium leaves a purple/pink flame.
Prefixes are used when naming compounds containing variable charge metal ions.
False; Prefixes are used when naming compounds containing covalent (molecular) bonds
How many significant figures does the number .02060 have?
4 sig figs
If a magnet sticks to an item, it is probably made of gold.
False; Pure gold is not magnetic, if a magnet is attracted to gold, then it probably has iron to it, and therefore not pure gold.
Two nested coffee cups are used to make a ____________.
Calorimeter
How will a fake gold piece react with the test acids?
Change color
Specific heat is the amount of heat needed to raise the temperature of one mole of a substance by 1C.
False; Specific heat is the amount of heat needed to raise its temperature by 1C per gram
SO2 is called sulfate.
False; Sulfur dioxide
If an object floats in syrup, it will float in oil.
False; Syrup creates more buoyancy in water than oil.
The liquid filtered off the solid is called the precipitate.
False; The liquid filtered off the solid is called the filtrate.
The colors of fireworks comes from the metal salt components.
False; The result of the amount of energy that was absorbed and released by the metal's electrons, an amount characteristic of that particular metal.
Water is a good substance for a radiator because it has a very low specific heat.
False; Water is a good substance for a radiator because it has a very high specific heat
You should never tare a balance
False; always
Iron compounds tend to be highly colored.
False; darker colored
Water at 0 degrees Celsius is colder to touch than water at 32 degrees Fahrenheit
False; it's the same
D = V/m
False; m/V
A compound is soluble when it is not strongly attracted to water molecules.
False
A jeweler knows an item is 14K gold if the 14K test acid dissolves its mark on the touch stone.
False
A molecule with four atoms bonded to a central atom will have 90 angles.
False
Corrosion involves the change of a metal to its metal cation.
False
Natural substances are safe and have no side effects.
False
Purification usually results in more of the compound than what you started with.
False
The change from a solid to a liquid is one evidence that a chemical reaction has taken place
False
We would be better off in a world with no chemicals.
False
One cm^3 equals 10 mm^3
False; 1 cm^3 = 1000 mm^3
There are 1000 grams in a milligram
False; 1 gram = 1000 milligrams
A roman numeral in a name indicates the subscript number in the chemical formula.
False; A roman number in a name indicates the charge number
CaCO3 is named calcium carbon trioxide.
False; CaCO3 is called calcium carbonate
A Celsius degree represents a larger temperature change than a Fahrenheit degree
False; Celsius is 0-100 and Fahrenheit is 32-212
Density is an extensive property.
False; Density is an intensive property.
The density of ice is 1.00 g/mL.
False; Density of ice = 0.92 g/mL
All metals sink in water.
False; Ex: Aluminium
Fool's gold will leave a yellow streak on an unglazed white porcelain tile.
False; Fool's gold will leave a greenish black color.
Hand warmers make use of endothermic reactions.
False; Hand warmers make use of exothermic reactions
Alcohols contain carboxyl groups.
False; Hydroxyl
If a reaction is endothermic, its ΔH will be negative.
False; If a reaction is endothermic, its ΔH will be positive.
Metal component names appear to the right in compound names.
False; Metal component names appear to the left in compound names
The curved surface at the top of a column of water in a graduated cylinder is called a __________ .
Meniscus
What gases are products of a combustion reaction?
Methane and Oxygen
What metal is contained in the most common fool's gold?
Pyrite
The heat of reaction is known as ____________ and symbolized as ____________.
enthalpy change ΔH
q S m ΔT
heat specific heat mass change in temperature
Solubility is an example of a ________________ property.
physical