CHEM 120 (chem120)

What is the correct order of melting points for the following alkanes, from highest to lowest temperature? correct answer: heptane > hexane > ethane > methane 2. Given an alkane that contains 25 carbon atoms. How many hydrogen atoms are present in its structure? a) correct answer: ) 52 3. Which of the following properly describes constitutional (structural) isomers? correct answer: compounds with the same molecular formula, but a different order of attachment of atoms 4. How...

molecular mass (molecular weight) correct answer: the sum of the atomic masses, in atomic mass units, of all the atoms in the formula of a compound empirical formula correct answer: a chemical formula showing the ratio of elements in a compound rather than the total number of atoms Avogadro's number (Mole) correct answer: 6.02 x 10^23 proton correct answer: A subatomic particle that has a positive charge and that is found in the nucleus of an atom neutron correct answer: A suba...

define matter correct answer: anything that has mass and takes up space what is not considered matter? correct answer: light, heat, electricity definite shape, definite volume correct answer: solid indefinite shape, definite volume correct answer: liquid indefinite shape, indefinite volume correct answer: gas pure substance correct answer: one substance; definite and constant composition; can't be separated into 2 kinds of matter by physical means; single kind of matter ...

Levelling Effect correct answer: the inability of a solvent to differentiate amongst the relative strength of all acids OH- correct answer: the strongest base possible H3O+ correct answer: the strongest acid possible Differentiating effect correct answer: the ability of a solvent to differentiate among the relative strengths of all acids Common Ion Effect correct answer: the shift in equilibrium caused by the addition of a compound having an ion in common with the dissolved subs...

Which of these contributions did alchemists of the Middle Ages make to modern science? correct answer: -Sun-centered universe and metallurgy -Metallurgy and the development of scientific techniques -The scientific method and law of conservation of mass -Law of conservation of matter and first atomic theory -Law of conservation of mass and law of constant composition Which of these is the best definition of a scientific hypothesis? correct answer: -A prediction based on a limited number ...

What is a good scientific definition of a chemical? correct answer: Chemical- any substance made up of one or more elements from the periodic table What is the difficulty in defining the chemical industry in terms of the periodic chart? correct answer: The definition of a chemical is too broad. Too much would be included in the chemical industry. What is the chief source of the chemicals known as inorganic chemicals? correct answer: Inorganic chemicals come from ores and minerals mined ...

chemistry correct answer: the science that tries to understand how matter behaves by studying how atoms and molecules behave scientific method correct answer: ways of learning that emphasizes observation and experimentation (self correcting) observation correct answer: we go out in nature and ask questions we measure or observe some aspect of nature hypothesis correct answer: tentative interpretation of an observation law correct answer: summarizes a large number of observations...

How many bonds can nitrogen have? Which rule or principle should be used? A) Five bonds; octet rule. B) Three bonds; octet rule. C) Three bonds; the Hund's rule. D) Five bonds; the Aufbau Principle. correct answer: B When two hydrogen atoms meet, they will attract to each other and form a bond (and a H2 molecule). Why? A) Because electrons like to stay together. B) Because electrons like to be paired up. C) Because there is attraction between the electron in one hydrogen atom an...

Significant Figure correct answer: a digit that is either reliably known or closely estimated conversion factors correct answer: relationship between two quantities expressed as a fraction (1 inch/2.45cm) element correct answer: the most basic form of matter that exists under ordinary condidtions compound correct answer: a unique, pure substance that is composed of two or more elements which are chemically combined atom correct answer: smallest fundamental particle of an eleme...

SI unit for Temperature correct answer: C F correct answer: (9/5 C) + 32 C correct answer: 5/9 (F -32) K correct answer: C+273.15 density correct answer: mass/volume 1 mL correct answer: =1cm^3 = 1cc percent error correct answer: difference from known value/known value x 100 sig fig for Addition/Subtraction correct answer: answer has the same number of decimal places as the factor with the least amount of decimal places sig fig rules for multiplication/ division c...