Answer:
166 g
Explanation:
Step 1: Write the reaction for the obtaining of Fe from magnetite
Fe₃O₄ ⇒ 3 Fe + 2 O₂
Step 2: Calculate the moles corresponding to 120 g of Fe
The molar mass of Fe is 55.85 g/mol.
120 g × (1 mol/55.85 g) = 2.15 mol
Step 3: Calculate the moles of Fe₃O₄ required to produce 2.15 moles of Fe
The molar ratio of Fe₃O₄ to Fe is 1:3. The moles of Fe₃O₄ required are 1/3 × 2.15 mol = 0.717 mol
Step 4: Calculate the mass corresponding to 0.717 moles of Fe₃O₄
The molar mass of Fe₃O₄ is 231.53 g/mol.
0.717 mol × 231.53 g/mol = 166 g
<u>Answer:</u> The amount of energy released per gram of 
is -71.92 kJ
<u>Explanation:</u>
For the given chemical reaction:
The equation used to calculate enthalpy change is of a reaction is:
![\Delta H^o_{rxn}=\sum [n\times \Delta H^o_f_{(product)}]-\sum [n\times \Delta H^o_f_{(reactant)}]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28product%29%7D%5D-%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28reactant%29%7D%5D)
The equation for the enthalpy change of the above reaction is:
![\Delta H^o_{rxn}=[(5\times \Delta H^o_f_{(B_2O_3(s))})+(9\times \Delta H^o_f_{(H_2O(l))})]-[(2\times \Delta H^o_f_{(B_5H_9(l))})+(12\times \Delta H^o_f_{(O_2(g))})]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%285%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28B_2O_3%28s%29%29%7D%29%2B%289%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28H_2O%28l%29%29%7D%29%5D-%5B%282%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28B_5H_9%28l%29%29%7D%29%2B%2812%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28O_2%28g%29%29%7D%29%5D)
Taking the standard enthalpy of formation:
Putting values in above equation, we get:
![\Delta H^o_{rxn}=[(5\times (1271.94))+(9\times (-285.83))]-[(2\times (73.2))+(12\times (0))]\\\\\Delta H^o_{rxn}=-9078.57kJ](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%285%5Ctimes%20%281271.94%29%29%2B%289%5Ctimes%20%28-285.83%29%29%5D-%5B%282%5Ctimes%20%2873.2%29%29%2B%2812%5Ctimes%20%280%29%29%5D%5C%5C%5C%5C%5CDelta%20H%5Eo_%7Brxn%7D%3D-9078.57kJ)
We know that:
Molar mass of pentaborane -9 = 63.12 g/mol
By Stoichiometry of the reaction:
If 2 moles of produces -9078.57 kJ of energy.
Or,
If 
of produces -9078.57 kJ of energy
Then, 1 gram of will produce = 
of energy.
Hence, the amount of energy released per gram of is -71.92 kJ
Explanation:
Once blood glucose levels increase, pancreatic insulin migrates into a fat cell via the blood stream. Insulin then binds in the plasma membrane of the cell to an Insulin Receptor (IR). Through autophosphorylation, phosphate groups are then added to the IR, causing GLUT4 molecules to come to the cell's surface.
There are so many routes by which water can move through the various stages in the water cycle.
<h3>What is the water cycle?</h3>
The water cycle has to do with the route of movement of water in the enviroment. We have to note that there are so many routes by which water can move through the various stages in the water cycle.
The sun supplies the energy that drives the water cycle. This is seen in the fact that the supply of energy from the sun is required for evaporation to take place.
Learn more about water cycle:brainly.com/question/1151425
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