Answer: they both contain the same metal(calcium)
Explanation: calcium burns with a characteristic orange color.
Explanation:
(1) CuF2+Mg-------->MgF2+Cu
(2) 2Na+2H2O --------> 2NaOH+H2
(3) 2KBr+Cl2-------->2KCl+Br2
Answer:
Enthalpy change for the reaction is -67716 J/mol.
Explanation:
Number of moles of
in 50.0 mL of 0.100 M of 
= Number of moles of HCl in 50.0 mL of 0.100 M of HCl
=
moles
= 0.00500 moles
According to balanced equation, 1 mol of
reacts with 1 mol of HCl to form 1 mol of AgCl.
So, 0.00500 moles of
react with 0.00500 moles of HCl to form 0.00500 moles of AgCl
Total volume of solution = (50.0+50.0) mL = 100.0 mL
So, mass of solution = (
) g = 100 g
Enthalpy change for the reaction = -(heat released during reaction)/(number of moles of AgCl formed)
=
= ![\frac{-100g\times 4.18\frac{J}{g.^{0}\textrm{C}}\times [24.21-23.40]^{0}\textrm{C}}{0.00500mol}](https://tex.z-dn.net/?f=%5Cfrac%7B-100g%5Ctimes%204.18%5Cfrac%7BJ%7D%7Bg.%5E%7B0%7D%5Ctextrm%7BC%7D%7D%5Ctimes%20%5B24.21-23.40%5D%5E%7B0%7D%5Ctextrm%7BC%7D%7D%7B0.00500mol%7D)
= -67716 J/mol
[m = mass, c = specific heat capacity,
= change in temperature and negative sign is included as it is an exothermic reaction]
a. We first calculate the moles of sucrose needed
moles sucrose = 0.250 M * 0.25 L
moles sucrose = 0.0625 mol
The molar mass of sucrose 342.3 g/mol, so the mass of
sucrose needed is:
mass sucrose = 0.0625 mol * 342.3 g/mol
mass sucrose = 21.4 grams
So simply dissolved about 21.4 grams of sucrose in 250 mL
solution.
b. We use the formula:
M1 V1 = M2 V2
1.50 M * V1 = 0.100 M * 0.350 L
V1 = 0.0233 L = 23.3 mL
So simply take 23.3 mL of solution from 1.50 M then dilute
it with water until 350 mL to make 0.100 M.
Balanced chemical reaction: 2Na(s) + F₂(g) → 2NaF(s) + energy.
This is exothermic reaction (energy or heat is released), because reactants have higher energy than products of reaction.
In ionic salt sodium fluoride (NaF), fluorine has electronegativity approximately χ = 4 and sodium χ = 1 (Δχ = 4 - 1; Δχ = 3), fluorine attracts electron and it has negative charge and sodium has positive charge.