Answer: Option (4) is the correct answer.
Explanation:
A mixture is defined as a substance that contains two or more different substance that are physically mixed with each other.
If solute particles are evenly distributed in a solvent then it is known as a homogeneous mixture.
For example, salt dissolved in water is a homogeneous mixture.
If solute particles are unevenly distributed into the solvent then it is known as a heterogeneous mixture.
For example, sand in water is a heterogeneous mixture.
Thus, we can conclude that the statement a mixture must contain at least two different substances, is correct about mixtures.
Answer:
The reaction would shift toward the reactants
When the reaction reach equilibrium the partial pressure of NH3 will be greater than 1atm
Explanation:
For the reaction:
2NH₃(g) ⇄ N₂(g) + 3H₂(g)
Where K is defined as:

As initial pressures of all 3 gases is 1.0atm, reaction quotient, Q, is:

As Q > K, <em>the reaction will produce more NH₃ until Q = K consuming N₂ and H₂.</em>
Thus, there are true:
<h3>The reaction would shift toward the reactants</h3><h3>When the reaction reach equilibrium the partial pressure of NH3 will be greater than 1atm</h3>
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