The element with atomic number 12 is magnesium (Mg), and its electronic configuration is [Ne] 3s2.

The element with atomic number 15 is phosphorus (P), and its electronic configuration is [Ne] 3s2 3p3.

Chlorine (Cl) has the configuration 1s2 2s2 2p6 3s2 3p5.

The element with atomic number 20 is Calcium, which has the configuration [Ar] 4s2.

The element with atomic number 26 is iron (Fe), and its electronic configuration is [Ar] 4s2 3d6.

Copper (Cu) has the configuration [Ar] 4s2 3d9.

The electronic configuration of Zinc (atomic number 30) is [Ar] 4s2 3d10.

The electronic configuration of Lanthanum (atomic number 57) is [Xe] 6s2.

Iron (Fe) has 26 electrons, and its electronic configuration is [Ar] 4s2 3d6.

Nitrogen has 7 electrons, and its electronic configuration is 1s2 2s2 2p3.

The potassium ion (K+) loses one electron, resulting in the configuration 1s2 2s2 2p6.

Sodium ion (Na+) has lost one electron, resulting in the configuration 1s2 2s2 2p6.

Converting percentages to moles gives C: 40/12 = 3.33, H: 6.7/1 = 6.7, O: 53.3/16 = 3.33. The simplest ratio is 1:2:1, giving the empirical formula CH2O.

Convert percentages to grams (assume 100 g total): 40 g C, 6.7 g H, 53.3 g O. Convert to moles: C=3.33, H=6.67, O=3.33. The simplest ratio is 1:2:1, giving CH2O.

The empirical formula is the simplest whole number ratio, which is CH2O.

The empirical formula is the simplest whole number ratio of the elements in a compound. For glucose, it is CH2O.

The energy band gap of silicon at room temperature is approximately 1.1 eV.

The energy difference between n=1 and n=2 in hydrogen is 10.2 eV.

The energy of the photon can be calculated using the Rydberg formula. The transition from n=3 to n=2 emits a photon of energy approximately 1.89 eV.

The energy of a photon is given by E = hf. Using h = 6.63 x 10^-34 J.s, E = 6.63 x 10^-34 * 5 x 10^14 = 3.31 x 10^-19 J.

The energy of a photon is given by E = hν. Substituting the values gives E = 6.63 x 10^-34 J.s * 5 x 10^14 Hz = 3.31 x 10^-19 J.

The energy of a photon is given by E = h * f, where h = 6.63 x 10^-34 J·s. Thus, E = 6.63 x 10^-34 * 6 x 10^14 = 4.14 x 10^-19 J.

The energy of a photon is given by E = hc/λ. Using h = 6.626 x 10^-34 J·s and c = 3 x 10^8 m/s, E = (6.626 x 10^-34)(3 x 10^8)/(500 x 10^-9) = 3.98 eV.

The energy of the ground state of a hydrogen atom is -13.6 eV.

U = 1/2 * C * V² = 1/2 * (10 × 10^-6 F) * (50 V)² = 0.0125 J.

The energy (U) stored in a capacitor is given by the formula U = 1/2 CV².

The energy (U) stored in a capacitor is given by the formula U = 1/2 CV².

The energy (U) stored in a capacitor is given by the formula U = 1/2 CV².

The standard enthalpy of formation of CO2 is -393.5 kJ/mol.

The formation of water from hydrogen and oxygen is an exothermic reaction, resulting in a negative enthalpy change.