Answer:
B)
Explanation:
UV increases earths temp making global warming
They should be recycled but not reused because the "repeated use increases the risk of leaching and bacterial growth." Also, recycling PET plastic "results in reduced energy consumption, lower cost, and reduced environmental impact."
Answer:
See explanation
Explanation:
Hydrogen has only one valence electron. Sometimes, hydrogen is included as part of group 1 or 17 in the periodic table. Is this correct? Well, the answer to this question is not so straight forward!
Let us remember that hydrogen forms a univalent positive ion H^+ just like the group 1 elements, but it also forms a univalent negative ion H^- just like group 17 elements. Also, hydrogen is a gas and forms a molecular diatomic compound just like group 17 elements. This is not the case with other group 1 elements. We can see that hydrogen is chemically and physically dissimilar to other group 1 elements hence one can logically argue against its inclusion in group 1. Also, it is not a halogen, so we can also argue against its inclusion in group 17.
However, it is convenient to include hydrogen in the main groups 1 or 17 when discussing its chemical properties in order to make it easier to assimilate. If we place hydrogen in group 1, we can understand that it forms univalent positive ions. Similarly, if we place it in group 17, we understand that it forms univalent negative ions.
Most times hydrogen is just written separately at the top right corner of the periodic table and not as a member of any group because of the issues outlined above.
D) The enzyme and substrate form an enzyme-substrate complex
An enzyme is a protein molecule that acts as a catalyst in biological reactions. It does so by acting on a substrate which is specific to its shape. The substrate binds to the enzyme's active site, forming the enzyme-substrate complex. The reaction is then complete and the product detaches from the enzyme molecule. The enzyme is then free to act on other substrate molecules.
it will turn red when placed into an acid and if it is placed into a base, it will turn blue