Answer:
The student's conclusion is not correct
Explanation:
Activation energy is the minimum amount of energy required for a reaction to occur. All reactions require there activation energy to be met before the reaction can proceed. When the temperature of a reaction is increased, the kinetic energy of the reactant molecules increases; colliding more with each other, which makes them "surmount" the activation energy of the reaction faster as compared to a lower temperature.
In combustion, there is burning of an hydrocarbon (in this case propane) in excess oxygen. The burning assists in increasing the kinetic energy of the reactant particles which in turn easily surmounts the activation energy of the reaction by colliding (effective collision) more with oxygen. So, the reaction has an activation energy but the activation energy has been met and passed and hence the reaction is proceeding faster.
Increasing the temperature of a reaction is one of the ways of increasing the rate of a chemical reaction.
Answer:
C. 0.20 M Mg ion & 0.40 M Cl ion
Explanation:
MgCl₂ is a ionic salt which is dissociated as this
MgCl₂ → Mg²⁺ + 2Cl⁻
First of all, we have a solution of 200 mL, with [MgCl₂] = 0.6M
Molarity . volume = moles.
0.6 mol/l . 0.2l = 0.12 mol
MgCl₂ → Mg²⁺ + 2Cl⁻
0.12mol 0.12 0.24
This moles are also in 400mL of water, so the new concentration is
[Mg²⁺] = 0.12 m/0.6L = 0.2M
[Cl⁻] = 0.24 m/0.6L = 0.4M
Remember we initially have 200mL and then, we add 400 mL, so we supose aditive volume. (600mL)
<u>Answer:</u>
Law used: Combined Gas Law
<u>Explanation:</u>
We are given the following problem:
Carbon dioxide is in a steel tank at 20°C, 10 liters and 1 atm. What is the pressure on the gas when the tank is heated to 100°C?
To solve this, the most appropriate law that can be used it Combined Gas Law, which is the result of combining the Boyle's law, Charles' law, and Gay-Lussac's law together.
Answer : The molar mass of the solute would be low.
Explanation :
Formula used for depression in freezing point is:
where,
= change in freezing point
= freezing point of solution
= freezing point of water
i = Van't Hoff factor
= freezing point constant
m = molality
= mass of solute
= mass of solvent
= molar mass of solute
From the formula we conclude that, when the freezing point of the solution read incorrectly that is freezing point of the solution is lower than the true freezing point then this means that change in freezing point would be high and the molar mass of the solute would be low.
Hence, the molar mass of the solute would be low.
