Answer:
46.85kJ
Explanation:
The specific latent heat of vaporization of water is =2.3 x 10⁶ J kg-1.
The specific heat capacity of water = 4.2×10³J/kgK
The latent heat of fusion of water= 3.36×10⁵ J/kg
The specific heat capacity of ice=2.108×10³ J/kgK
The heat of lost due to cooling of ice is calculated as follows by adding the heat lost during condensation of water vapor to the heat lost during cooling the water to freezing point plus the heat lost during freezing plus the heat lost during cooling the ice to -32.0°C
=MLv+MCΔT(water)+MLf+MCΔT(ice) where Lv=latent heat of vaporization of water , and Lf is the latent heat of fusion ice.
=(0.015kg×2.3 x 10⁶ J/kg)+(0.015kg×4.2×10³J/kgK×100K)+(0.015kg×3.36×10⁵ J/kg)+(0.015kg× 2.108×10³ J/kgK)×32K
=34500J+6300J+5040J+1011.84J
=46851.84J
=46.85kJ
Hey there!:
Molar mass of Mg(OH)2 = 58.33 g/mol
number of moles Mg(OH)2 :
moles of Mg(OH)2 = 30.6 / 58.33 => 0.5246 moles
Molar mass of H3PO4 = 97.99 g/mol
number of moles H3PO4:
moles of Mg(OH)2 = 63.6 / 97.99 => 0.649 moles
Balanced chemical equation is:
3 Mg(OH)2 + 2 H3PO4 ---> Mg3(PO4)2 + 6 H2O
3 mol of Mg(OH)2 reacts with 2 mol of H3PO4 ,for 0.5246 moles of Mg(OH)2, 0.3498 moles of H3PO4 is required , but we have 0.649 moles of H3PO4, so, Mg(OH)2 is limiting reagent !
Now , we will use Mg(OH)2 in further calculation .
Molar mass of Mg3(PO4)2 = 262.87 g/mol
According to balanced equation :
mol of Mg3(PO4)2 formed = (1/3)* moles of Mg(OH)2
= (1/3)*0.5246
= 0.1749 moles of Mg3(PO4)2
use :
mass of Mg3(PO4)2 = number of mol * molar mass
= 0.1749 * 262.87
= 46 g of Mg3(PO4)2
Therefore:
% yield = actual mass * 100 / theoretical mass
% = 34.7 * 100 / 46
% = 3470 / 46
= 75.5%
Hope that helps!
Answer:
Any element placed in a flame will change its color. Atoms are made of positively charged nuclei, about which negatively charged electrons move according to the laws of quantum mechanics. Quantum mechanics constrains them to appear in various distinct patterns, called orbitals. (Orbitals are a lot like planetary orbits, but blurrier, so that you're never quite sure just where the electrons are.)
Left on their own, the electrons of an atom tend to relax into orbitals that leave the atom with the lowest possible energy--its ground state. Putting atoms into a flame, though, adds energy to the looser electrons farthest from the nucleus and pushes them into other orbitals. Eventually, these excited electrons drop back to where they ought to be, and in so doing, they release the energy they stored up as particles of light, called photons.
Explanation:
The speed is 7,350km that's the speed of the car