Which of the following describes condensation polymerisation?Produces a polymer plus a small moleculeUsually involves two different monomersAll of theseThe functional groups on the two different monomers react together2Which of the following is a dioic acid? HOOC-CH2-COOHHO-CH2-OHCH3-CH2-COOHCH3-CH2-CH2-CH2-COOH3A diol is joined with a dioic acid in a condensation polymerisation reaction. What products are formed?Polyester onlyPoly(ethene) plus waterPoly(ethene) onlyPolyester plus water4What is the functional group of an ester?‒OH‒COOH‒COO‒C=C5In a condensation polymerisation reaction between nHO-□-OH and nHOOC-□-COOH, how many water molecules are formed?nH2O3nH2ONo water2nH2O6Which of the following is methanediol?OOC-CH2-COOHOOC-CH2-COOHHO-CH2CH2-OHHO-CH2-OH

The text you provided seems to be a set of multiple choice questions related to chemistry, specifically polymerisation. Here are the answers:

1. The correct answer is "All of these". Condensation polymerisation produces a polymer and a small molecule (usually water), involves two different monomers, and the functional groups on the two different monomers react together.

2. The dioic acid is HOOC-CH2-COOH. Dioic acids, also known as dicarboxylic acids, have two carboxyl groups (-COOH), which are present in this molecule.

3. The products formed when a diol is joined with a dioic acid in a condensation polymerisation reaction are "Polyester plus water". This is because condensation polymerisation results in the formation of a polymer (in this case, polyester) and a small molecule (in this case, water).

4. The functional group of an ester is ‒COO‒. Esters are characterized by a carbonyl adjacent to an ether group.

5. In a condensation polymerisation reaction between nHO-□-OH and nHOOC-□-COOH, "2nH2O" water molecules are formed. This is because each reaction between a diol and a dioic acid forms two water molecules.

6. Methanediol is HO-CH2-OH. Methanediol, also known as methylene glycol, has two hydroxyl groups (-OH) attached to a central carbon atom.