(Data are from Science 283 [February 26, 1999], p. 1296.) A) What is the probability that a randomly chosen sample of glass will break at less than 579 MPa? z(579) = (579-579)/14 = 0 P(x < 579) = P(z<0) = 0.5000 B) More than 590 MPa? z(590) = (590-579)/14= 11/14= 0.7857 P(x<500) = P(z< 0.7857) = 0.2160 C) Less Than 600 MPa?
Calculations and Conclusions A. 2.83/15 = 0.1887 12.8/44 = 0.2909 19.2/63 = 0.3048 B. 12.3 36.1 51.6 C. Atomic Mass = (0.123 x 0.1887) + (0.361 x 0.2909) + (0.516 x 0.3048) Answer: 0.2855 g D. None of the Bg atoms in the original sample would’ve been expected to have the same mass as the calculated atomic mass of the element because the Atomic mass is only the average of the different masses. E. 24.32 F. 63) (x) + (65) (1 - x) = 63.5 --- Cu-63=75% Cu-65=25% G. The atomic mass of copper is not exactly equal to 64 because the percent abundance isn’t equal. H.
This is the common mode of decay for heavy radioactive nuclides (those with atomic number, Z > 83). When a nucleus loses an alpha particle its mass number (A) decreases by 4 units and the atomic number (Z) decreases by 2 units. The product of an alpha decay is a nuclide with two less protons and neutrons, respectively, than the original nuclide. For example, uranium-238 ([pic]U) and radium-226 ([pic]Ra) decay by alpha particle emission, which change them to thorium-234 and radon-222, respectively.
None b. i only c. ii only d. i and ii e. ii and iii 5. For the positive integers a,b, and k, ak || b means that ak is a divisor of b, but ak+1 is not a divisor of b. If k is a positive integer and 2k || 72, then k is equal to p. 2 q. 3 r. 4 s. 8 t. 18 6. If p is the product of integers from 1 to 30, inclusive, what is the greatest integer k for which 3k is a factor of p?
Purpose of investigation: Picture 3 The purpose of this investigation was to see if concentration affects the rate of reaction between Magnesium and Hydrochloric acid. Magnesium is one of the key reactants in the experiment. Magnesium is a chemical element found in the periodic table with the chemical abbreviation of ‘Mg’.It is a soft, light, silver/white metal and has an atomic number of 12 and an atomic mass of 24 and is the eighth most abundant element on the earth [1]. It is an alkaline earth metal and consists of 12 protons, 12 neutrons and 12 electrons. However the number of neutrons differs as there are different isotopes of Magnesium (Mg, solid).
According to Bender oxygen and hydrogen are elements other than carbon used to define mole. A mole is the quantity of an element that weighs out in grams the amount of an element specified by the atomic weight. Work Cited Bodner , George M. "How was Avogadro's number determined?." scientific american. © 2013 Scientific American, a Division of Nature America, Inc., 16 Feb 2004.
3 On the periodic table, it rest between gold and thallium with an atomic number of 80. Some of its properties include a hefty atomic weight of 200.59, 1 a density of 13.59, freezing point of -38.85*C, and boiling point of 356.6*C. Mercury is not soluble in water, is somewhat volatile, and (as a liquid) has such a high surface tension that it will not “wet” surfaces. 3 Mercury was known to early civilizations such as the Egyptians, the Chinese, the Greeks and the Romans. 4 It was treated by these cultures with a mystical fascination and respect. In many cultures such as Tibetan and Indian, Mercury was thought by the alchemist the mystic to be the primordial element.
With a density of density 0.89990 g/liter. The freezing point of neon is -248.67° C, and the boiling point of neon is -246.048° C, which is even lower than the boiling point of nitrogen (-195.8°C). When under low pressure, neon emits a bright orange-red glow if a small electric current is passed through it. The electron configuration of neon is 1s22s22p6. The chemical properties of neon include the fact that it is not reactive because it has a full outer shell, and therefore cannot gain or lose any electrons.
Ordinary Tin is composed of ten stable isotopes, which is the largest amount in the periodic table. Thirteen unstable isotopes have been recognized. Tin shows chemical similarity to both neighboring group 14 elements. It can be located between elements: indium and antimony(side by side) and between Germanium and Lead (top and bottom) The Atomic mass of Tin is 50, which is a “magic number” in nuclear physics. There are 28 additional unstable isotopes that are known.
At the dirac point in graphene electrons and holes have zero effective mass due to the linear relation between energy and movement at low energies. Thus electronic mobility of graphene is very high more than that of silver. Mechanical properties: Another of graphene’s stand-out properties is its inherent strength. Due to the strength of its 0.142 nm-long carbon bonds, graphene is the strongest material ever discovered, with an ultimate tensile strength of 130,000,000,000 Pascals which is four times strength of structural steel [3]. It is also very light at 0.77milligrams per square metre (for comparison purposes, 1 square metre of paper is roughly 1000 times heavier).