Your answer will be B)5.00*10^-5. Hope it helps.
Answer:
Number of neutrons: 44
Number of protons: 34
Number of electrons: 36
Explanation:
The atomic number of Se (Selenium) is 34
Mass number is 78
Number of neutrons = mass number - atomic number = 78 - 34 = 44
Number of protons is the same as the atomic number
Number of protons = 34
Selenium ion has a charge of -2. This means it accepts two more electrons
Number of electrons = atomic number + 2 = 34 + 2 = 36
Answer:

Explanation:
Hello,
In this case, the undergoing chemical reaction is:

Next, we compute the reacting moles of each reactants:


Then, as magnesium and hydrohloric acid are in a 1:2 molar ratio 0.153 moles of magnesium will completely react with 0.306 moles of hydrochloric acid yet we only have 0.144 moles, therefore, limiting reactant is hydrochloric acid. Thus, we compute the produced moles of hydrogen:

Finally, we use the ideal gas equation with T=298K and 1atm (STP conditions) to compute the liters of hydrogen gas:

Best regards.
Answer:
:O Fr? Bet let me go get them lol
Answer:
CF4
Molecular geometry- tetrahedral
Electron geometry- tetrahedral
NF3
-molecular geometry - trigonal pyramidal
Electron geometry - tetrahedral
OF2
Molecular geometry - bent
Molecular geometry - tetrahedral
H2S
Molecular geometry- bent
Electron geometry - tetrahedral
Explanation:
According to Valence Shell Electron Pair Repulsion Theory, the shape of a molecule depends on the number of electron pairs on the valence shell of the central atom in the molecule.
For all the compounds listed, the central atom has four points of electron density. This correspond to a tetrahedra electron pair geometry. The presence of lone pairs on the central atom of OF2,NF3 and H2S accounts for the departure of the observed molecular geometry from the geometry and idealized bond angle predicted on the basis of the VSEPR theory.