Answer:
Iron (Fe)
Explanation:
The number of electrons (-) is usually the same as the number of protons (+) in the atom of the element (unless it is an ion).
The element described has 26 electrons, so we can assume that it has 26 protons as well. The number of protons in an atom is the atomic number of element that the atom is.
Element 26 on the PTE is Iron (Fe), which does rust (oxidation) in air and water.
Answer:
2.51 x 1023 atoms C
Explanation:
MW C = 12.011
5g x (1mol/12.011g) =0.416 mol
0.416 mol x (6.022x10^23) = 2.51 x 1023 atoms C
Answer:
See explanation
Explanation:
The structure of ethylene is shown in the image attached. The two carbon atoms have a double covalent bond between them.
The two carbon atoms are sp2 hybridized. The bond between them is a covalent bond, there is one pi bond and one sigma bond between the carbon atoms. Between carbon and hydrogen, there are covalent bonds also. The covalent bonds are sigma bonds.
The pi bonds between carbon atoms is weaker than the sigma bonds between the carbon atoms. This is because, the side-by-side overlap the p orbitals in a pi bond is less effective than the end-to-end overlap of a sigma bond.
Answer:
90.3 kJ/mol
Explanation:
Let's consider the following thermochemical equation.
2 NO(g) + O₂(g) → 2 NO₂(g) ∆H°rxn = –114.2 kJ
We can find the standard enthalpy of formation for NO using the following expression.
∆H°rxn = 2 mol × ΔH°f(NO₂(g)) - 2 mol × ΔH°f(NO(g)) - 1 mol × ΔH°f(O₂(g))
∆H°rxn = 2 mol × ΔH°f(NO₂(g)) - 2 mol × ΔH°f(NO(g)) - 1 mol × 0 kJ/mol
∆H°rxn = 2 mol × ΔH°f(NO₂(g)) - 2 mol × ΔH°f(NO(g))
ΔH°f(NO(g)) = (2 mol × ΔH°f(NO₂(g)) - ∆H°rxn) / 2 mol
ΔH°f(NO(g)) = (2 mol × 33.2 kJ/mol + 114.2 kJ) / 2 mol
ΔH°f(NO(g)) = 90.3 kJ/mol
Answer:
hi! merry xmas!
Explanation:
Condensation is the process where water vapor becomes liquid. It is the reverse of evaporation, where liquid water becomes a vapor.
Condensation happens one of two ways: Either the air is cooled to its dew point or it becomes so saturated with water vapor that it cannot hold any more water.
