KCl: 74.5g/mol
Molarity = mol/Liters
Since you are given 0.750L and 1.50M, we can plug it into the molarity formula and solve for moles.
1.50M = x mol/0.750L
X = 1.125 moles of KCl needed
You asked for grams so let’s convert the moles of KCl to grams:
1.125 mol x (74.5g/mol) = 83.8g KCl
Answer:
reaction 1 and reaction 4 both are decomposition reactions
while reaction 2 is double displacement reaction and reaction 3 and 5 are combination reactions
Is there an equation? I can't help if there's no equation involved.
Answer:
B.) If sodium carbonate is added to vinegar, the reaction will absorb heat.
Explanation:
A.) is incorrect because this is not testable. Rather, it is just an opinion that cannot be proven correct or incorrect.
B.) is correct because this statement is testable. Tests need to be run to determine the accuracy of the statement.
C.) is incorrect because this statement explains something that does not need to be tested. It is an example of a physical change when one tears a piece of paper.
D.) is incorrect because this is already a true statement. It is obvious that not all reactions absorb/release heat. While tests could be run to further prove this statement true, it is already considered accurate.
Answer:
The final temperature of the solution is 44.8 °C
Explanation:
assuming no heat loss to the surroundings, all the heat of solution (due to the dissolving process) is absorbed by the same solution and therefore:
Q dis + Q sol = 0
Using tables , can be found that the heat of solution of CaCl2 at 25°C (≈24.7 °C) is q dis= -83.3 KJ/mol . And the molecular weight is
M = 1*40 g/mol + 2* 35.45 g/mol = 110.9 g/mol
Q dis = q dis * n = q dis * m/M = -83.3 KJ/mol * 13.1 g/110.9 gr/mol = -9.84 KJ
Qdis= -9.84 KJ
Also Qsol = ms * Cs * (T - Ti)
therefore
ms * Cs * (T - Ti) + Qdis = 0
T= Ti - Qdis * (ms * Cs )^-1 =24.7 °C - (-9.84 KJ/mol)/[(104 g + 13.1 g)* 4.18 J/g°C] *1000 J/KJ
T= 44.8 °C
