The uncertainties of the delta measurements and the uncertainty of the atomic weight derivedfrom the best measurement of isotopic abundances constrain the number of significant figures in theatomic-weight values of the upper and lower bounds. For carbon, the fifth digit after the decimal pointis uncertain because of the uncertainty value of 0.000 027. Therefore, the number of significant digitsin the atomic-weight value is reduced to four figures after the decimal point. The Commission may rec-ommend additional conservatism and reduce the number of significant figures further. For the lowerbound of carbon, 12.009 635 is truncated to 12.0096. For an upper bound, the trailing digit is increasedto ensure the atomic-weight interval encompasses the atomic-weight values of all normal materials. Inthe case of carbon, the upper bound is adjusted from 12.011 532 to 12.0116 to express four digits afterthe decimal point. The lower and upper bounds are evaluated so that the number of significant digits ineach is identical. If a value ends with a zero, it may need to be included in the value to express therequired number of digits. The following are examples of lower and upper atomic-weight bounds foroxygen that could be published by the Commission in its various tables.
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Extracted from" Atomic weights of the elements 2009 (IUPAC Technical Report)"
Crude oil was formed by hydrocarbons or distillate from decaying animal matter migrating to stratigraphic traps like folds in the sedimentary rocks like anticlines which are dome-shaped folds in the rocks.
In North America, the First Nations used the pitchy tar sands near Fort McMurray to waterproof their canoes long ago before the white man arrived.
In Alberta, the first successful oil well to be drilled was in approximately 1947 called the Leduc well and then oil drilling blossomed from there. Crude oil would be refined to process this oil at that time and broken down into fractions.
Large scale expansion of the oil industry got impetus from the widespread use of automobiles and planes in the early part of the 20th century and then once discoveries like the Leduc well were made, then it became apparent that it was possible to figure out where the oil was and then it blossomed.
In 1907. Leo Baekeland invented bakelite from petroleum ie a polymer.
Nylon and polyester were developed from petroleum in the 1930's and 1941 respectively.,
In 1865, Edward Roberts, an American discovered that by exploding a torpedo with explosive powder in it in an oil well it could increase the well yield by up to 1200%
Peak oil is estimated to be very soon between 2010 and 2030 or most likely before 2020 so anytime soon and after that the reserves are expected to diminish. The world should be converting strongly to alternative energy sources the sooner the better especially to prevent the potential pollution of pipelines and oil tankersl
.
Burning less fossil fuels and riding bikes or walking instead of cars.
Explanation:
Answer:
2Ca₃(PO₄)₂ + 10C + 6SiO₂ → 6CaSiO₃ + P₄ + 10CO.
Explanation:
- To balance a chemical reaction, we should apply the law of conservation of mass.
- Law of conversation of mass states that the no. of atoms is equal in both sides of the chemical reaction.
- So, the balanced chemical reaction is:
<em>2Ca₃(PO₄)₂ + 10C + 6SiO₂ → 6CaSiO₃ + P₄ + 10CO.</em>
that 2 mol of Ca₃(PO₄)₂ react with 10 mol of C and 6 mol of SiO₂ to produce 6 mol of CaSiO₃, 1 mol of P₄ and 10 mol of CO.
Answer:
The standard cell potential of the reaction is 0.78 Volts.
Explanation:
Reduction at cathode :
Reduction potential of 
to Cu=
Oxidation at anode:
Reduction potential of 
to Fe=
To calculate the 
of the reaction, we use the equation:
Putting values in above equation, we get:
The standard cell potential of the reaction is 0.78 Volts.
