Answer:
Friedrich Mohs who is a German mineralogist
Inefficiency of the material or engine causes the output work of a machine to be less
than the input work. It is governed by the second law of thermodynamics wherein
no product of work can produce 100 percent efficiency. Only the Carnot engine
can produce a 100 percent effieciency.
The balanced equation for the above reaction is as follows
CaCO₃ + 2HBr ---> CaBr₂ + CO₂ + H₂O
stoichiometry of CaCO₃ to HBr is 1:2
number of moles of CaCO₃ reacted - 5.64 g / 100 g/mol = 0.0564 mol
according to molar ratio
number of HBr moles - 0.0564 mol x 2 = 0.1128 mol
number of HBr moles in 250.0 mL - 0.1128 mol
therefore number of HBr moles in 1000 mL - 0.1128 mol / 250.0 mL x 1000 mL = 0.4512 mol
molarity of HBr - 0.4512 M
Answer:
D. 3.844 x 10^5
3.844 is between 1 and 10, so that is correct.
Not C because if it is negative it would be a decimal from 0 e.g -> 0.88
Answer:
The limiting reagent is the SF₄
Explanation:
In order to determine the limiting reagent we convert the mass of the reactants to moles, and then, we work with stoichiometry.
4.687 g / 108.06 g/mol = 0.0433 moles of SF₄
6.281 g / 333.8 g/mol = 0.0188 moles of I₂O₅
The reaction is: 5SF₄ + 2I₂O₅ = 4IF₅ + 5SO₂
Ratio is 5:2. 5 moles of fluoride react with 2 moles of pentoxide
Then, 0.0433 moles of fluoride will react with (0.0433 . 2) / 5 = 0.0173 moles
We have 0.0188 moles of I₂O₅ and we need 0.0173 so there are some moles of pentoxide that remains after the reaction. In conclussion, the limiting reagent is the SF₄. We verify:
2 moles of pentoxide react with 5 moles of SF₄
Therefore, 0.0188 moles of I₂O₅ will react with (0.0188 . 5) / 2 = 0.0470 moles.
As we have 0.0433 moles of SF₄, we do not have enough moles.