<span>Divide the number of grams present in the sample by copper's gram atomic weight to find the number of gram atomic weights present. Then multiply that result by Avogadro's Number: 6.022137 x 10^23 atoms/gram atomic weight.1,200 g/(63.54 g/gram atomic weight) ? 18.885741 gram-atomic weights. Hope this helps. </span>
Answer:
the ionic radius of the anion 
Explanation:
From the diagram shown below :
The anion
is located at the corners
The cation
is located at the body center
The Body diagonal length = 
∴ 
Given that :
(i.e the ratio of the ionic radius of the cation to the ionic radius of
the anion )

Also ; a = 664 pm
Then :

Therefore, the ionic radius of the anion 
The activation energy barrier is 40.1 kJ·mol⁻¹
Use the Arrhenius equation






Salt lowers the freezing/melting point of water, so in both cases the idea is to take advantage of the lower melting point. Ice forms when the temperature of water reaches 32 degrees Fahrenheit (0 degrees Celsius).
Answer:
The system gains 126100 J
Explanation:
The heat can be calculated by the equation:
Q = nxCxΔT, where Q is the heat, C is the heat capacity,n is the number of moles and ΔT is the variation of temperature (final - initial). The number of moles is the mass divided by the molar mass, so:
n = 250/4 = 62.5 mol.
The system must be in thermal equilibrium with the surroundings, so if the temperature of the surroundings decreased 97 K, the temperature of the system increased by 97 K, so ΔT = 97 K
Q = 62.5x20.8x97
Q = 126100 J