reaction
r stands for "the rest of a molecule". Since there are about 20 different amino acids, it could be any one of the 20.
In organic chemistry, the R and S configurations are used to describe the spatial arrangement of atoms around a chiral center. The R configuration indicates a clockwise arrangement of substituents, while the S configuration indicates a counterclockwise arrangement.
In organic chemistry, the R and S configurations refer to the spatial arrangement of atoms around a chiral center. The R configuration indicates a clockwise arrangement of substituents, while the S configuration indicates a counterclockwise arrangement. This distinction helps to identify the stereochemistry of molecules.
It is shared by Yves Chauvin, Robert H. Grubbs and Richard R. Schrock.
Richard R. Schrock won the Nobel Prize in Chemistry in 2005 for his work on the development of the metathesis method in organic synthesis. This method allows for the efficient and environmentally friendly production of complex molecules, which has had a significant impact on the fields of pharmaceuticals, materials science, and biotechnology.
To factor the expression 4qr - qr^3, we first notice that both terms have a common factor of qr. We can factor out qr to get qr(4 - r^2). Next, we recognize that 4 - r^2 is a difference of squares, which can be factored further as (2 + r)(2 - r). Therefore, the fully factored form of 4qr - qr^3 is qr(2 + r)(2 - r).
In chemistry, this chemical compound, R-134A is the symbol for tetrafluoroethane. Tetrafluoroethane can be used as a solvent in organic chemistry.
↔QR
Suppose p/q and r/s are rational numbers where p, q, r and s are integers and q, s are non-zero.Then p/q + r/s = ps/qs + qr/qs = (ps + qr)/qs. Since p, q, r, s are integers, then ps and qr are integers, and therefore (ps + qr) is an integer. q and s are non-zero integers and so qs is a non-zero integer. Consequently, (ps + qr)/qs is a ratio of two integers in which the denominator is non-zero. That is, the sum is rational.
This isn't a question, even. It's a statement about a line segment, QR.
R. A. Witthaus has written: 'Essentials of chemistry' -- subject(s): Organic Chemistry, Chemistry, Pharmaceutical chemistry
Suppose x and y are two rational numbers. Therefore x = p/q and y = r/s where p, q, r and s are integers and q and s are not zero.Then x - y = p/q - r/s = ps/qs - qr/qs = (ps - qr)/qsBy the closure of the set of integers under multiplication, ps, qr and qs are all integers,by the closure of the set of integers under subtraction, (ps - qr) is an integer,and by the multiplicative properties of 0, qs is non zero.Therefore (ps - qr)/qs satisfies the requirements of a rational number.
William R. Robinson has written: 'Chemistry' -- subject(s): Chemistry 'General chemistry with qualitative analysis' -- subject(s): Analytic Chemistry, Chemistry, Chemistry, Analytic, Qualitative
Suppose A and B are two rational numbers. So A = p/q where p and q are integers and q > 0 and B = r/s where r and s are integers and s > 0. Then A - B = p/q - r/s = ps/qs - qr/qs = (ps - qr)/qs Now, p,q,r,s are integers so ps and qr are integers and so x = ps-qr is an integer and y = qs is an integer which is > 0 Thus A-B can be written as a ratio of two integers, x/y where y>0. Therefore, A-B is rational.
Suppose p/q and r/s are rational numbers where p, q, r and s are integers and q, s are non-zero.Then p/q + r/s = ps/qs + qr/qs = (ps + qr)/qs.Since p, q, r, s are integers, then ps and qr are integers, and therefore (ps + qr) is an integer.q and s are non-zero integers and so qs is a non-zero integer.Consequently, (ps + qr)/qs is a ratio of two integers in which the denominator is non-zero. That is, the sum is rational.Also p/q * r/s = pr/qs.Since p, q, r, s are integers, then pr and qs are integers.q and s are non-zero integers so qs is a non-zero integer.Consequently, pr/qs is a ratio of two integers in which the denominator is non-zero. That is, the sum is rational.
John R. Amend has written: 'General, organic, and biological chemistry' -- subject(s): Biochemistry, Chemistry, Chemistry, Organic, Organic Chemistry
R. Nelson Smith has written: 'Chemistry; a quantitative approach' -- subject(s): Analytic Chemistry, Chemistry, Quantitative