Answer:
- <u><em>The first statement is false: a.At equilibrium, equal amounts of products and reactants are present. ΔG° is a function of Keq.</em></u>
Explanation:
When one part of a statement is false, the whole statement is false.
At <em>equilibrium,</em> the amounts of products and reactants does not have to be equal.
At equlibrium the rates of the forward reaction and the reverse reaction must be equal.
An equilibrium reaction may be represented by:
That represents two reactions:
- Direct reaction: A + B → C + D (A and B yield C and D)
- Reverse reaction: A + B ← C + D (C and D yield A and B: note that the arrow goes from right to left)
So, it is when the direct and the forward rates are equal that there is not net change in the amounts of all the species and so the reaction is is equilibrium).
As per the other statement, both parts are true:
- When reactants become products, they do so through an intermediate transitrion state: when the reactants approach each other and collide with enough energy and appropiate position, the bonds start to break and the bonds of the products start to form. This is the transition state.
- Most biocatalysts are proteins: enzymes are simply proteins, with specific structures, that may accelerate or even deceralate biochemical reactions.
Answer:
2. Option B.
Explanation:
H₂SO₄ + Ba(OH)₂ → BaSO₄ + 2H₂O
You can count 2H in sulfuric acid and 2 H in the barium hyrdoxide, so the coefficient for water must be 2.
You will have 4 H on both sides of the reaction.
Try with the dissociations of each reactant
Sulfuric acid ⇒ H₂SO₄ → 2H⁺ + SO₄⁻²
Barium hydroxide ⇒ Ba(OH)₂ → Ba²⁺ + 2OH⁻
Sulfate anion bonds to barium cation to produce the salt, therefore the 2 protons will bond the 2 hydroxide in order to produce, 2 moles of H₂O
2H⁺ + 2OH⁻ → 2H₂O
A catalyst will ALWAYS increase the reaction rate so C
Answer:
B
Explanation:
Statement A
Vrms (root-mean-square velocity) is defined as follows.
Vrms = √(2RT/Mm), where R is the ideal gas constant, T is the temperature, and Mm is the molar mass of the gas. R and T are the same for both gases, but the molar mass is different, so Vrms for the two gases is different
Statement B
Kinetic energy KE of a molecule is related to temperature as follows:
KE = 3/2KbT, where Kb is the Boltzmann's constant and T is the temperature. The temperature is the same for both gases, so KE is the same for both.
Statement C
The rate depends on the number of molecules present. Since there are twice as many molecules of methane as propane, the rate is different for both gases.
Statement D
Pressure is directly proportional to the number of moles, based on the ideal gas law (pV = nRT). The volume and temperature are the same for both gases, so since there are twice as many molecules of methane as propane, the pressure is twice as great in the cylinder of methane.
<span>In order to determine the mass of the piece of copper with only knowing it's density, it must have it's volume measured. In order to do this, the piece of copper could be placed in a container filled to the brim with a spout and a graduated cylinder below the spout. Then the piece of copper can be placed into the container without any fingers in the water. Then water will displace into the cylinder, the measured volume is the volume of the piece of copper, because of Archimede's principle, and we assume that the water is 1.0 g/mL or 1 g/cm^3. Then multiply the density with the volume to get the mass of the piece of copper.</span>