Why are K3[Cr(C2O4)3].3H2O, K2[Cu(C2O4)2].2H2O and K3[Fe(C2O4)3].3H2O coloured, whereas K3[Al(C2O4)3.3H2O is colourless?
1 answer:
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Answer:
The answer is
<h3>6000 N/m² or 6000 Pa</h3>Explanation:
The pressure exerted by an object given the force of the object and the area can be found by using the formula
where
P is the pressure
f is the force
a is the area
From the question
f = 2400 N
a = 0.4 m²
So we have
We have the final answer as
<h3>6000 N/m² or 6000 Pa</h3>Hope this helps you
Answer:
B. BF₃
Explanation:
All the molecules have polar bonds, but a molecule will be nonpolar if the molecule has the symmetry that makes the bond dipoles cancel.
To make the decision, we must
- Draw the Lewis structure
- Assign the VSEPR electron geometry
- Determine the molecular shape.
- Examine the symmetry of the molecule
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<em>A. Water </em>
Lewis structure = H-O-H (2 bonding pairs, 2 lone pairs)
Electron geometry = AX₂E₂ tetrahedral
Molecular geometry = bent
Symmetry (see Figure A): The two O-H bonds are polar, with their negative ends pointing towards the O. The horizontal components of the bond dipoles cancel, but the vertical components reinforce each other and give an upward pointing molecular dipole. This is a <em>polar molecule with polar bonds</em>.
===============
<em>B. Boron trifluoride </em>
Lewis structure = BF₃ (3 bonding pairs)
Electron geometry = AX₃, trigonal planar
Molecular geometry = trigonal planar
Symmetry (see Figure B): The three B-F bonds are polar, with their negative ends pointing towards the F. The horizontal components of the bond dipoles cancel, but the vertical components of the two downward -pointing dipoles reinforce each other and give a resultant that is equal and opposite to the upward dipole. Thus, the bond dipoles cancel. This is a nonpolar molecule with polar bonds.
===============
<em>C. Ammonia</em>
Lewis structure = :NH₃ (3 bonding pairs, 1 lone pairs)
Electron geometry = AX₃E, tetrahedral
Molecular geometry = trigonal pyramidal
Symmetry (see Figure C): The three N-H bonds are polar, with their negative ends pointing towards the N. The horizontal components of the bond dipoles cancel, but the vertical components reinforce each other and give an upward pointing molecular dipole. This is a <em>polar molecule with polar bonds</em>.
===============
<em>D. Nitrogen trichloride </em>
Lewis structure = :NCl₃ (3 bonding pairs, 1 lone pair)
Electron geometry = AX₃E, tetrahedral
Molecular geometry = trigonal pyramidal
Symmetry (see Figure D): The three N-Cl bonds are polar, with their negative ends pointing towards the Cl. The horizontal components of the bond dipoles cancel, but the vertical components reinforce each other and give a downward pointing molecular dipole. This is a <em>polar molecule with polar bonds</em>.
===============
<em>E. Dichloromethane </em>
Lewis structure = H₂CCl₂ (4 bonding pairs)
Electron geometry = AX₄, tetrahedral
Molecular geometry = tetrahedral
Symmetry (see Figure E): The two C-H bonds are nonpolar, but the two C-Cl bonds are polar with their negative ends pointing towards the Cl. The horizontal components of the bond dipoles cancel, but the vertical components reinforce each other and give a downward pointing molecular dipole. This is a <em>polar molecule with polar bonds</em>.
