Answer:
a process that involves rearrangement of the molecular or ionic structure of a substance, as distinct from a change in physical form or a nuclear reaction
Nuclear fusion in the sun involves hydrogen (H) atoms
combining to form helium (He). A student claims that since the atmosphere
contains hydrogen, any fusion reaction on Earth would result in an uncontrolled
chain reaction. What is wrong in the student’s reasoning is that the uncontrolled
chain reactions can only happen during nuclear fission.
The answer is “the sustainability of the ecosystem” because if the ecosystem isn’t sustainable enough for many different organisms to live in it then the biological diversity of the ecosystem will decrease.
Answer:
C₃H₄O₄
Explanation:
In order to get the empirical formula of a compound, we have to follow a series of steps.
Step 1: Divide the percent by mass of each element by its atomic mass.
C: 34.6/12.01 = 2.88
H: 3.9/1.01 = 3.86
O: 61.5/16.00 = 3.84
Step 2: Divide all the numbers by the smallest one, i.e., 2.88
C: 2.88/2.88 = 1
H: 3.86/2.88 ≈ 1.34
O: 3.84/2.88 ≈ 1.33
Step 3: Multiply all the numbers by a number that makes all of them integer
C: 1 × 3 = 3
H: 1.34 × 3 = 4
O: 1.33 × 3 = 4
The empirical formula is C₃H₄O₄.
Answer:
The lock-and-key model:
c. Enzyme active site has a rigid structure complementary
The induced-fit model:
a. Enzyme conformation changes when it binds the substrate so the active site fits the substrate.
Common to both The lock-and-key model and The induced-fit model:
b. Substrate binds to the enzyme at the active site, forming an enzyme-substrate complex.
d. Substrate binds to the enzyme through non-covalent interactions
Explanation:
Generally, the catalytic power of enzymes are due to transient covalent bonds formed between an enzyme's catalytic functional group and a substrate as well as non-covalent interactions between substrate and enzyme which lowers the activation energy of the reaction. This applies to both the lock-and-key model as well as induced-fit mode of enzyme catalysis.
The lock and key model of enzyme catalysis and specificity proposes that enzymes are structurally complementary to their substrates such that they fit like a lock and key. This complementary nature of the enzyme and its substrates ensures that only a substrate that is complementary to the enzyme's active site can bind to it for catalysis to proceed. this is known as the specificity of an enzyme to a particular substrate.
The induced-fit mode proposes that binding of substrate to the active site of an enzyme induces conformational changes in the enzyme which better positions various functional groups on the enzyme into the proper position to catalyse the reaction.
