Answer:
Lithium oxide, Li₂O.
Explanation:
Hello!
In this case, according to the given amounts, it is possible to write down the chemical reaction as shown below:
Which means that the metallic oxide has the following formula: M₂O. Next, we can set up the following proportional factors according to the chemical reaction:
Thus, we perform the operations in order to obtain:
So we solve for x as shown below:
Whose molar mass corresponds to lithium, and therefore, the metallic oxide is lithium oxide, Li₂O.
Best regards!
Answer:
The enthalpy change of the reaction is -66.88 kJ/mol.
Explanation:
Mass of the solution = m = 100 g
Heat capacity of the solution = c = 4.18 J/g°C
Initial temperature of the solutions before mixing = 
Final temperature of the solution after mixing = 
Heat gained by the solution due to heat released by reaction between HCl and silver nitrate = Q


Heat released due to reaction = Q' =-Q = -334.4 J
Moles of silver nitrate = n
Molarity of silver nitrate solution = 0.100 M
Volume of the silver nitrate solution = 50.0 mL = 0.050 L ( 1 mL = 0.001 L)


Enthalpy change of the reaction = 

1 J = 0.001 kJ
The enthalpy change of the reaction is -66.88 kJ/mol.
Answer is: <span>1.0 mol X left over.
</span>Chemical reaction: X + 2Y → XY₂.
n(X) = 3,0 mol, excess reactant.
n(Y) = 4,0 mol, limiting reagent.
n - amount of substance.
from reaction: n(X) : n(Y) = 1 : 2.
n(X) : 4 mol = 1 : 2.
n(X) = 2 mol, that reacts.
excess of X: 3 mol - 2 mol = 1 mol.