<h3><u>Answer;</u></h3>
C. increasing the surface area of Fe2O3
<h3><u>Explanation;</u></h3>
- The rate of reaction refers to the speed at which products are formed from reactants.
- The rate of any chemical reaction depends on a number of factors which include, surface area, temperature, concentration of reactants among others.
- <em><u>When solids and liquids react, increasing the surface area of the solid will increase the rate of reaction. Thus, decrease in the size of particles causes an increase in the total surface area of the solid and therefore increasing the rate of reaction.</u></em>
The Star gets stretched and torn apart by the gravitational pull of the black whole, stellar material gets compressed as it is pulled in, this is called, stellar tidal disruption
<u>Answer:</u> The amount of heat released when 0.211 moles of 
reacts is 554.8 kJ
<u>Explanation:</u>
The chemical equation for the reaction of 
with oxygen gas follows:
The equation for the enthalpy change of the above reaction is:
![\Delta H_{rxn}=[(5\times \Delta H_f_{(B_2O_3(s))})+(9\times \Delta H_f_{(H_2O(l))})]-[(2\times \Delta H_f_{(B_5H_9(l))})+(12\times \Delta H_f_{(O_2(g))})]](https://tex.z-dn.net/?f=%5CDelta%20H_%7Brxn%7D%3D%5B%285%5Ctimes%20%5CDelta%20H_f_%7B%28B_2O_3%28s%29%29%7D%29%2B%289%5Ctimes%20%5CDelta%20H_f_%7B%28H_2O%28l%29%29%7D%29%5D-%5B%282%5Ctimes%20%5CDelta%20H_f_%7B%28B_5H_9%28l%29%29%7D%29%2B%2812%5Ctimes%20%5CDelta%20H_f_%7B%28O_2%28g%29%29%7D%29%5D)
We are given:
Putting values in above equation, we get:
![\Delta H_{rxn}=[(2\times (-1272))+(9\times (-285.4))]-[(2\times (73.2))+(12\times (0))]\\\\\Delta H_{rxn}=-5259kJ](https://tex.z-dn.net/?f=%5CDelta%20H_%7Brxn%7D%3D%5B%282%5Ctimes%20%28-1272%29%29%2B%289%5Ctimes%20%28-285.4%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_%7Brxn%7D%3D-5259kJ)
To calculate the amount of heat released for the given amount of , we use unitary method, we get:
When 2 moles of reacts, the amount of heat released is 5259 kJ
So, when 0.211 moles of will react, the amount of heat released will be = 
Hence, the amount of heat released when 0.211 moles of reacts is 554.8 kJ
Answer:
mass = 0.907865 grams
Explanation:
From the periodic table:
molar mass of Li = 6.941 grams
molar mass of F = 18.998 grams
Therefore:
molar mass of LiF = 6.941 + 18.998 = 25.939 grams/mole
number of moles can be calculated as follows:
number of moles = mass / molar mass
We have:
number of moles = 0.035 moles
molar mass = 25.939 grams/mole
Substitute in the equation to get the mass as follows:
0.035 = mass / 25.939
mass = 0.035 * 25.939 = 0.907865 grams
Hope this helps :)
