The given reaction is a combustion reaction, since a hydrocarbon is burning in presence of oxygen
Answer:
C. Tip had the lower pressure, it was 652.71mmHg
Explanation:
To answer this question you need to convert both values into a common unit so you can compare directly.
87kPa = 652.71 mmHg
Answer:
459.126 grams of calcium chloride is needed to prepare 2.657 L of a 1.56 M solution
Explanation:
Molarity is a measure of the concentration of a solute in a solution that indicates the amount of moles of solute that appear dissolved in one liter of the mixture. In other words, molarity is the number of moles of solute that are dissolved in a given volume.
The Molarity of a solution is determined by the following expression:

Molarity is expressed in units 
In this case:
- Molarity: 1.56 M= 1.56

- Number of moles of calcium chlorine= ?
- Volume= 2.657 liters
Replacing:

Solving:
Number of moles of calcium chlorine= 1.56 M* 2.657 liters
Number of moles of calcium chlorine= 4.14 moles
In other side, you know:
- Ca: 40 g/mole
- Cl: 35.45 g/mole
Then the molar mass of the calcium chloride CaCl₂ is:
CaCl₂= 40 g/mole + 2* 35.45 g/mole= 110.9 g/mole
Now it is possible to apply the following rule of three: if in 1 mole there is 110.9 g of CaCl₂, in 4.14 moles of the compound how much mass is there?

mass= 459.126 g
<u><em>459.126 grams of calcium chloride is needed to prepare 2.657 L of a 1.56 M solution</em></u>
Answer:
Option C. 88 KJ
Explanation:
The activation energy (Ea) is the minimum energy that reactant must overcome in order for them to proceed to product.
In an energy profile diagram, the activation energy (Ea) is obtained by calculating the difference between the energy of the activation complex (i.e peak) and the energy of the reactant.
With the above information, we shall determine the activation energy (Ea) of the reaction above as follow:
Activation complex = 268.74 KJ
Energy of reactant = 180.74 KJ
Activation energy (Ea) =?
Activation energy = Activation complex – Energy of reactant
Activation energy = 268.74 – 180.74
Activation energy = 88 KJ
Therefore, the activation energy (Ea) of the reaction is 88 KJ