Chem 110 - Test 2
Which of the following parts of Dalton's atomic theory has been modified in light of later discoveries? A) Atoms are indivisible B) Chemical reactions involve rearrangement of atoms C) All matter is made up of very small particles called atoms D) Compounds are formed from atoms
A) Atoms are indivisible
Mendeleev's periodic table organized elements in a systematic way. Which of the following attempted to arrange elements in a systematic way and can be considered a "precursor" of the modern periodic table? A) Dobereiner's Triads B) Dalton's Atomic Theory C) Dalton's Atomic Masses D) Berzelius's Atomic Weights
A) Dobereiner's Triads
The ancient Greeks believed that matter was composed of four basic elements. Which of the following was NOT one of the four? A) Mercury B) Water C) Earth D) air
A) Mercury
Methane can be decomposed into two simpler substances, hydrogen and carbon. Therefore, methane
cannot be an element.
Lavoisier measured the mass of substances before and after chemical reactions and summarized his observations in a(n)
law.
Nitrogen forms a number of different compounds with oxygen, depending upon the experimental conditions. This type of observation concerning the behavior of matter is summarized by
the Law of Multiple Proportions.
Lavoisier performed many of the same experiments as his predecessors. The one thing that most distinguished Lavoisier's work was
the mass measurements
Perhaps the greatest triumph of Mendeleev's periodic table was
the prediction of the existence of undiscovered elements
After many observations, Proust stated that elements combine in definite proportions to form compounds. Dalton explained these observations by proposing that matter must consist of atoms Dalton's explanation is called a(n)
theory
The Greek word for atomos means
uncuttable
32 g of sulfur will react with 48 g of oxygen to produce 80 g of sulfur trioxide. If 16 g of sulfur and 100 g of oxygen are placed into a sealed container and allowed to react, what is the mass of the material in the container after the reaction is completed?
116 g
How many years ago was an atomic view of matter first proposed?
2500
Assume that you have a new "triad" of elements (A,B,C) with similar properties. A is the smallest element and has a mass of 30 u. C is the largest element and has a mass of 90 u. The mass of B would be approximately __________ u.
60
Which one of the following statements is NOT a correct statement of the Law of Conservation of Mass? A) The mass of a system is dependent upon chemical reactions that may occur B) Matter cannot be created nor destroyed C) Atoms are conserved in chemical reactions D) The mass of a system is conserved in a chemical reaction
A) The mass of a system is dependent upon chemical reactions that may occur
Which philosopher believed that matter was continuous and was not made up of atoms?
Aristotle
Although all parts of Dalton's atomic theory are important, which one of the postulates is crucial to explain the observations summarized by the Law of Definite Proportions?
Atoms combine with other atoms in fixed, whole number ratios to form compounds
Leucippus and Democritus believed that all of the following statements about matter were true EXCEPT A) Substances are mixtures of different kinds of atoms B) Matter was continuous C) Each type of matter had distinctive size and shape D) Matter was made up of atoms
B) Matter was continuous
The scientist who in 1828 published a table of atomic weights containing 54 elements was
Berzelius
Which of the following was NOT explained by Dalton's atomic theory? A) the difference between elements and compounds B) the Law of Conservation of Mass C) the difference between isotopes of an element D) the Law of Multiple Proportions
C) the difference between isotopes of an element
Which of the following postulates of Dalton's atomic theory has been modified in light of later discoveries? A) Chemical reactions involve rearrangement of atoms B) Compounds are formed from atoms C) All matter is made up of very small particles called atoms D) All atoms of an element are identical
D) All atoms of an element are identical
___ was the first person to propose a consistent "modern" atomic theory
Dalton
No matter how much extra oxygen is available, 12 grams of carbon always combines with 32 grams of oxygen. This best illustrates the Law of
Definite Proportions.
The "father of modern chemistry" is
Lavoisier
The Law of Definite Proportions was first stated by
Proust
CO2 always contains 3 g of C for every 8 g of O. This is an example of
Proust's Law of Definite Proportions
(True/False) Democritus thought that real substances were mixtures of various types of atoms.
True
(True/False) Dobereiner's Triads and Mendeleev's Periodic Table were both based on the idea that properties of elements tended to repeat.
True
(True/False) Germanium was discovered in 1886. Its existence had been predicted by Mendeleev
True
(True/False) The Law of Constant Composition and the Law of Definite Proportions are different names for the same phenomenon
True
Mendeleev arranged elements in the periodic table primarily in order of their
atomic masses
The amount of carbon on the earth, including the atmosphere,
is essentially constant
Atoms of the same element that have different masses are called
isotopes
If drops of water are subdivided to the ultimately smallest drops possible, what is the smallest particle of water that retains the chemical and physical properties of water?
molecule.
Leucippus and Democritus proposed the "first" atomic view of matter. They arrived at this view based on
philosophical and intuitive speculation.
When Mendeleev developed his periodic table, he placed the greatest emphasis on
putting elements with similar properties in the same column