The answer is (3). The powdered iron and the piece iron is the same substance and is just different in the shape. So the reason is the power has larger surface area for reaction occurs.
Answer:
P₄O₆
Explanation:
The molecular formula is a whole number multiple of the empirical formula. that is, if the mole wt is 219.9 gms/mole and the empirical formula weight is 110 gms/mole*, then the whole number multiple is 219.9/110 = 2 => Molecular formula => (P₂O₄)₂ => P₄O₆.
I think the Ksp for Calcium Carbonate is around 5×10⁻⁹
(I don't know if this is the Ksp value that you use because I read somewhere that this value can vary. You should probably check with your teacher with what Ksp value they want you to use)
the equation for the dissociation CaCO₃ in water is CaCO₃(s)⇄Ca²⁺(aq)+CO₃²⁻(aq) which means that the concentration of Ca²⁺ is equal to the concentration of CO₃²⁻ in solution. For every molecule of CaCO₃ that dissolves, one atom of Ca²⁺ and one molecule of CO₃²⁻ is put into solution which is why the concentrations are equal in solution.
Since Ksp=[Ca²⁺][CO₃²⁻] and we know that [Ca²⁺]=[CO₃²⁻] we can rewrite the equation as Ksp=x² since if you say that [Ca²⁺]=[CO₃²⁻] when you multiply them together you get the concentration squared (I am calling the concentration x for right now).
when solving for x:
5×10⁻⁹=x²
x=0.0000707
Therefore [Ca²⁺]=[CO₃²⁻]=0.0000707mol/L which also shows how much calcium carbonate is dissolved per liter of water since the amount of Ca²⁺ and CO₃²⁻ in solution came from the calcium in a 1 to 1 molar ratio as shown in the equation (the value we found for x is the molar solubility of calcium carbonate).
Using the fact that the molar mass of calcium carbonate is 100.09g/mol you can use dimensional analysis as fallows:
(0.0000707mol/L)(100.09g/mol)=0.007077g/L
That means that there is 0.007077g of Calcium carbonate that can precipitate out of 1L of water.
since the question is asking for how much water needs to be evaporated to precipitate 100mg (0.1g) of Calcium you have to do the fallowing calculation:
(0.1g)/(0.007077g/L)=14.13L of water.
14.13L of water needs to evaporate in order to precipitate out 100mg of calcium carbonate
These types of questions can get long and confusing so I bolded parts that were important to try to guide you through it more easily.
I hope this helps. Let me know if anything is unclear.
Answer:
i think its b
Explanation:
if you removed the C02 from the atmosphere that
willl make the 02 and it will
released for the atmosphere
which means, Photosynthesis removes CO2 from the atmosphere and replaces it with O2. Respiration takes O2 from the atmosphere and replaces it with CO2. However, these processes are not in balance. Not all organic matter is oxidized. photosynthesis mean if you dont know: Photosynthesis – plants produce their own food in the form of glucose using the process of photosynthesis. This process uses sunlight (and so only occurs during the day) to remove carbon dioxide from the atmosphere and release oxygen.
this is why the CO2 is removed and the 02 is released into the atmosphere, Consumers such as animals, fungi, and bacteria get their energy from this excess biomass either while living or dead and decaying. Oxygen from the atmosphere is combined with carbohydrates to liberate the stored energy. ... Photosynthesis removes CO2 from the atmosphere and replaces it with O2.
and if the CO2 is release from the atmosphere this will happen --> Carbon dioxide causes about 20 percent of Earth's greenhouse effect; water vapor accounts for about 50 percent; and clouds account for 25 percent. ... Likewise, when carbon dioxide concentrations rise, air temperatures go up, and more water vapor evaporates into the atmosphere—which then amplifies greenhouse heating CO2 effects the wither, Scientists say that if CO2 doubles, it could raise the average global temperature of the Earth between two and five degrees Celsius. We are already increasing the amount of energy that bounces back to the Earth. Because of the greenhouse effect, this is causing global warming with its many destructive impacts. im sorry that i gave alot of facts my teacher said its good to add alot of facts some of my thoughts thank you i hope you get this right :)
Answer:
Explanation:
E = (hc)/(λ)
E = (6.624x10^(-27))Js x ((3×10^8)ms^(-1)) /
(77.8x10^(-9)m)
E = 2.55 x 10^(-11) J
