Specif gravity = density of the material / density of water
density of the material = specific gravity * density of water
density of gold = 19.3 * 1 g/mL = 19.3 g/mL
density = mass / volume ==> Volume = mass / density
Volume = 0.4 kg * 1000 g/kg / 19.3 g/mL = 20.725 mL
Length of one side of the cube =
![\sqrt[3]{20.725 {cm}^{3} }](https://tex.z-dn.net/?f=%20%5Csqrt%5B3%5D%7B20.725%20%7Bcm%7D%5E%7B3%7D%20%7D%20)
= 2.75 cm
Pass cm to inches
2.75 cm * 1 inch / 2.54 cm = 1.08 inch
Answer:
Rutherford's atomic model explained how the electrons surrounded the nucleus of protons and neutrons. His model showed how J. J. Thomson's Plum Pudding model was incorrect.
Nothing happens because a physical change only changes the appearance of the substance, whereas a chemical change transforms the substance into something completely different.
i.e. (chemical change) wood + fire = ash
(physical change) wood + axe = smaller pieces of wood
Answer:
Explanation:
For the reaction
C2H5OH (l) + 3 O2(g) = 2CO2(g) + 3 H2O
We can calculate the standard molar enthalpy of combustion using the standard enthalpies of formation of the species involved in the reaction according to Hess law:
ΔHºc = 2ΔHºf CO2 (g) + 3ΔHºfH2O(l) - ( ΔHºf C2H5OH (l) - 3ΔHºfO2 (g) )
( we were not give the water state but we know we are at standard conditions so it is in its liquid state )
The ΔHºfs can be found in appropiate reference or texts.
ΔHºc = 2ΔHºf CO2 (g)+ 3ΔHºfH2O(l) - ( ΔHºf C2H5OH (l) -+3ΔHºfO2 (g) )
= [ 2 ( -393.52 ) + 3 ( -285.83 ) ] - [( -276.2 + 0 ) ] kJ
ΔHºc = -1368.33 kJ