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4 years ago

When the equation HCl + MnO2 → MnCl2 + H2O + Cl2 is balanced, what is the coefficient for HCl? Question 6 options: 2 3 1 4

2 answers:

5 0

<span>HCl + MnO2 → MnCl2 + H2O + Cl2
To balance this reaction, we have to have an exact number of electrons of each element on both sides. So it will turn into:

4HCl + MnO2 </span>→ MnCl2 + 2H2O + Cl2

From that, we could see that the coefficient for the HCL is 4.

Vsevolod [243]4 years ago

4 0

the coefficient is 4 i took the test

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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:

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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

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4 years ago

5.11 g of MgSO₄ is placed into 100.0 mL of water. The water's temperature increases by 6.70°C. Calculate ∆H, in kJ/mol, for the

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To calculate the entalpy, we use the equation:

$q=mc\Delta T$

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q = heat absorbed by water = ?

m = mass of water = ${\text {volume of water}}\times {\text {density of water}}=100.0ml\times 1.00g/ml=100.0g$

c = heat capacity of water = 4.186 J/g°C

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When heat is absorbed, the sign of heat is taken to be positive and when heat is released, the sign of heat is taken to be negative.

The heat absorbed by water will be equal to heat released by $MgSO_4$

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

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Molar mass = 120 g/mol

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$\text{Moles of }MgSO_4=\frac{5.11g}{120g/mol}=0.042mol$

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