<span>Important information to solve the exercise :
Substance ΔHf (kJ/mol):
HCl(g)= −92.0 </span><span>kJ/mol
Al(OH)3(s)= −1277.0 </span><span><span>kJ/mol
</span> H2O(l)= −285.8 </span><span>kJ/mol
AlCl3(s) =−705.6 </span><span>kJ/mol
</span><span>Al(OH)3(s)+3HCl(g)→AlCl3(s)+3H2O(l)
reactants products
products- reactants:</span><span>
(−705.6) + (3 x −285.8) - ( −1277.0 ) - (3 x −92.0 ) = - 10.0 </span>kJ per mole at 25°C
<span>
</span>
B
Explanation:
Burning is a chemical change and cutting grass is a physical change
Answer:
2.75 mol
Explanation:
Given data:
Mass of Nitrogen = 38.5 g
Moles of ammonia produced = ?
Solution:
Chemical equation:
N₂ + 3H₂ → 2NH₃
Number of moles of nitrogen:
Number of moles = mass/ molar mass
Number of moles = 38.5 g/ 28 g/mol
Number of moles = 1.375 mol
Now we will compare the moles of ammonia and nitrogen from balance chemical equation.
N₂ : NH₃
1 : 2
1.375 : 2×1.375 = 2.75 mol
Thus 2.75 moles of ammonia are produced from 38.5 g of nitrogen.
Answer:
2.52 g NaCl
Explanation:
(Step 1)
To find the mass, you first need to find the moles NaCl. This value can be found using the molarity ratio:
Molarity = moles / volume (L)
After you convert mL to L, you can plug the given values into the equation and simplify to find moles.
136.9 mL / 1,000 = 0.1369 L
Molarity = moles / volume
0.315 M = moles / 0.1369 L
0.0431 = moles
(Step 2)
Now, you can use the molar mass to convert moles to grams.
Molar Mass (NaCl): 22.990 g/mol + 35.453 g/mol
Molar Mass (NaCl): 58.443 g/mol
0.0431 moles NaCl 58.443 g
------------------------------ x ------------------- = 2.52 g NaCl
1 mole
H2S donates a proton, therefore it is a Brønsted-Lowry base; CH3NH2 accepts a proton, so it’s a Brønsted-Lowry base.
