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An ester of carboxylic acid.R stands for any group (organic or inorganic) and R′ stands for organyl group.. In chemistry, an ester is a compound derived from an acid (organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group (−OH) of that acid is replaced by an organyl group (−R).
The General Certificate of Secondary Education (GCSE) is an academic qualification in a range of subjects taken in England, Wales, and Northern Ireland, ...
GCSE Bitesize was launched in January 1998, covering seven subjects. For each subject, a one- or two-hour long TV programme would be broadcast overnight in the BBC Learning Zone block, and supporting material was available in books and on the BBC website. At the time, only around 9% of UK households had access to the internet at home.
The hydroxide anion adds to the carbonyl group of the ester. The immediate product is called an orthoester. Saponification part I. Expulsion of the alkoxide generates a carboxylic acid: Saponification part II. The alkoxide ion is a strong base so the proton is transferred from the carboxylic acid to the alkoxide ion, creating an alcohol:
This is a list of estrogen esters, or ester prodrugs of estrogens. It includes esters, as well as ethers , of steroidal estrogens like estradiol , estrone , and estriol and of nonsteroidal estrogens like the stilbestrols diethylstilbestrol and hexestrol .
In organic chemistry and biochemistry esters are the functional group (R'-COOR") consisting of an organic radical united with the residue of any oxygen acid, either organic or inorganic. An ester is a product of the reaction of an acid (usually organic) and an alcohol (the hydrogen of the acid R-COOH is replaced by an alkyl group R").
An ester of a carboxylic acid. R stands for any group (typically hydrogen or organyl) and R ′ stands for any organyl group. In chemistry, an ester is a compound derived from an acid (organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group (−OH) of that acid is replaced by an organyl group (R ′). [1]
The BBC Learning Zone (previously The Learning Zone) was an educational strand run by the BBC as an overnight service on BBC Two. It broadcast programming aimed at students in Primary, Secondary and Higher Education as well as to adult learners.