Coffee is acidic so the first one would be correct
CH4 + 2 O2 ---> CO2 + 2 H2O Q = 891,6 kJ / mol CH4
1 mol CH4 = 16 g
16 g ---- 891,6 kJ
x g ----- 272 kJ
x = 272 kJ × 16 g / 891,6 kJ = 4,88 g
You must burn 4,88 g of CH4.
:-) ;-)
The atomic mass would be 28.08535 amu. Multiply 27.9769 by .92297 = 25.803. Multiply 28.9765 by .046832 to get 1.357. Multiply 29.9738 by .03872 to get .925351136. Add 25.803 + 1.357 + .03872 to get 28.08535 amu
Answer: The Lattice energy is the energy required to separate an ionic solid into its component gaseous ions <em>or</em>
It is the energy released when gaseous ions combine to form an ionic solid.
Explanation:
The lattice energy depends on the ionization energies and electron affinities of atoms involved in the formation of the compound. The ionization energies and electron affinities also depends on the ionic radius and charges of the ions involved. As the ionic radius for cations <em>increases</em> down the groups, ionization energy <em>decreases</em>, whereas, as ionic radii <em>decreases</em> across the periods , ionization energy <em>increases</em>. The trend observed for anions is that as ionic radii <em>increase </em>down the groups, electron affinity <em>decreases. </em>Across the period, as ionic radii <em>increases</em> electron affinity <em>increases</em>. Also, as the charge on the ion <em>increases,</em> it leads to an <em>increase</em> in energy requirement/content.
Therefore, for compounds formed from cations and anions in the same period, the highest charged cation and anion will have the highest lattice energy. For example, among the following compounds: Al2O3 (aluminium oxide), AlCl3 (aluminium chloride), MgO, MgCl2 (magnesium chloride), NaCl, Na2O (sodium oxide); Al2O3(aluminium oxide) will have the highest lattice energy, thus will be hardest to break apart because its ions have the highest charge.
