Answer:
Reversible reactions exhibit the same reaction rate for forward and reverse reactions at equilibrium.
Reversible reactions exhibit constant concentrations of reactants and products at equilibrium
Explanation:
A reversible reaction is a reaction that can proceed in both forward and backward direction.
Equilibrium is attained in a chemical system when there is no observable change in the properties of the system.
At equilibrium, a reversible reaction is occurring in at same rate. That is, the forward and backward reaction is occurring at the same rate. As the rate of the forward and backward reaction remains the same, the concentrations of the reactants and products will also be the same in order for the equilibrium to be maintained.
To solve the question we will assume that the gas behaves like an ideal gas, that is to say, that there is no interaction between the molecules. Assuming ideal gas we can apply the following equation:

Where,
P is the pressure of the gas
V is the volume of the gas
n is the number of moles
R is a constant
T is the temperature
Now, we have two states, an initial state, and a final state. The conditions for each state will be.
Initial state (1)
P1=975Torr=1.28atm
V1=3.8L
T1=-18°C=255.15K
Final state(2), STP conditions
P2=1atm
T2=273.15K
V2=?
We will assume that the number of moles remains constant, so the nR term of the first equation will be constant. For each state, we will have:

Since nR is the same for both states, we can equate the equations and solve for V2:

We replace the known values:

At STP conditions the gas would occupy 5.2L. First option
The answer is Na-F. The F has highest electronegativity among these elements. So we need to find the element with smallest electronegativity. And this element is Na.
The Earth's core is the part of Earth in the middle of our planet. It has a solid inner coreand a liquid outer core.
Answer:
166 g/mol
Explanation:
Step 1: Write the neutralization reaction
H₂A + 2 NaOH ⇒ Na₂A + 2 H₂O
Step 2: Calculate the reacting moles of NaOH
48.3 mL of 0.0700 M NaOH react.
0.0483 L × 0.0700 mol/L = 3.38 × 10⁻³ mol
Step 3: Calculate the reacting moles of H₂A
The molar ratio of H₂A to NaOH is 1:2. The reacting moles of H₂A are 1/2 × 3.38 × 10⁻³ mol = 1.69 × 10⁻³ mol.
Step 4: Calculate the molar mass of H₂A
1.69 × 10⁻³ moles of H₂A have a mass of 0.281 g. The molar mass of H₂A is:
M = 0.281 g / 1.69 × 10⁻³ mol = 166 g/mol