28.02g ------ 1 mol
X g ------------ 4.60 mol
X = (28.02×4.60)/1
X = 128,892 g
Answer : The enthalpy change during the reaction is -6.48 kJ/mole
Explanation :
First we have to calculate the heat gained by the reaction.

where,
q = heat gained = ?
m = mass of water = 100 g
c = specific heat = 
= final temperature = 
= initial temperature = 
Now put all the given values in the above formula, we get:


Now we have to calculate the enthalpy change during the reaction.

where,
= enthalpy change = ?
q = heat gained = 23.4 kJ
n = number of moles barium chloride = 

Therefore, the enthalpy change during the reaction is -6.48 kJ/mole
Answer:
104.84 moles
Explanation:
Given data:
Moles of Boron produced = ?
Mass of B₂O₃ = 3650 g
Solution:
Chemical equation:
6K + B₂O₃ → 3K₂O + 2B
Number of moles of B₂O₃:
Number of moles = mass/ molar mass
Number of moles = 3650 g/ 69.63 g/mol
Number of moles = 52.42 mol
Now we will compare the moles of B₂O₃ with B from balance chemical equation:
B₂O₃ : B
1 : 2
52.42 : 2×52.42 = 104.84
Thus from 3650 g of B₂O₃ 104.84 moles of boron will produced.
Answer:
Final pressure = 2.3225 atm
Amontons’s law states that
At constant volume and number of molecules, the pressure of a given mass of gas is directly proportional to its temperature
Explanation:
Temperature causes increased excitement of gas molecules increasing the number of collisions with the walls of the container which is sensed as increase in pressure
Amontons’s law: P/T = Constant at constant V and n
That is P1/T1 = P2/T2
Where temperature is given in Kelvin
Hence T1 of 10°C = 273.15 + 10 = 283.15K
Also temperature T2 of 40°C = 313.15 K
Hence
P2 = (P1/T1)×T2 = (2.1/283.15)×313.15 = 2.3225 atm