Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: An ionic bond is the force of attraction that holds together oppositely charged ions. Ionic bonds form crystals instead of molecules. Table salt contains ionic bonds. Answer: ionic bond

A: What term means the force of attraction that holds together oppositely charged ions?
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Q: Passage: The dipeptide has a free amino group on one end of the molecule and a free carboxyl group on the other end. Each is capable of extending the chain through the formation of another peptide bond. The particular sequence of amino acids in a longer chain is called an amino acid sequence. By convention, the amino acid sequence is listed in the order such that the free amino group is on the left end of the molecule and the free carboxyl group is on the right end of the molecule. For example, suppose that a sequence of the amino acids glycine, tryptophan, and alanine is formed with the free amino group as part of the glycine and the free carboxyl group as part of the alanine. The amino acid sequence can be easily written using the abbreviations as Gly-Trp-Ala. This is a different sequence from Ala-Trp-Gly because the free amino and carboxyl groups would be on different amino acids in that case. Answer: amino acid sequence

A: What is the particular sequence of amino acids in a longer chain called?
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Q: Passage: Carbon taxes are taxes placed on products that produce carbon dioxide. An example of this is gasoline for your car. The taxes encourage people to use less fossil fuel. This naturally reduces carbon dioxide emissions. Answer: carbon taxes

A:
What do you call taxes placed on products that produce carbon dioxide?
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