Answer:
The electron geometry, molecular geometry and idealized bond angles for these molecules respectively are:
a. CF4: tetrahedral, tetrahedral and 109.5 degrees
b. NF3 tetrahedral, trigonal pyramidal and 102.5 degrees
c. OF2 tetrahedral, angular and 103 degrees
d. H2S tetrahedral, angular and 92.1 degrees
Explanation:
The electron geometry considers the bound atoms and unbound electron pairs to determine the geometry. The four molecules have four bound atoms and/or unbound electrons pairs, thus they have a tetrahedral geometry. On the other hand, the molecular geometry only considers the position of bound atoms to determine the geometry.
Between H3O and H2O, H2O has a smaller bond angle due to the two unbound electron pairs. The bond angle decrease as the number of unbound electron pairs increases in every molecule.
CO2 and CCl4 are both nonpolar because of the 3D geometry of the molecule. Each individual bond is polar but both molecules have symmetrical geometry so the dipole bonds are canceled.
CH3F is a polar molecule because the dipole between the C-H and C-F bonds are differents thus, besides the symmetrical geometry the dipole bonds are not canceled.
Burning is a chemical reaction
Answer:
Unevenly
Explanation:
Fresh water is distributed unevenly in both time and space.
Answer: 20 mg Te-99 remains after 12 hours.
Explanation: N(t) = N(0)*(1/2)^(t/t1/2)
N(t) = (80 mg)*(0.5)^(12/6)
N(t) = 20 mg remains after 12 hours
