Answer:
109.5°, 120°, 109.5°
Explanation:
The bond angles that are marked as a, b and c in the given molecules is in the order of :
Angle a : 109.5°
Nitrogen is 
hybridized and the geometry is tetrahedral. So the bond angle is 109.5°
Angle b : 120°
Carbon is 
hybridized, so the shape is trigonal planer and the bond angle is 120°
Angle c : 109.5°
Carbon is hybridized and the geometry is tetrahedral. The bond angle is 109.5°
For which of the following activities might you want to hire a chemist?
Answer: D. testing a rock sample for gold content
Which of the following procedures involves a physical change in one of the substances?
Answer: C. separating a salt solution by evaporating the water
MCu: 63,5 g/mol
4 × mCu = 63,5×4 = 254 g
254g ------ 0,39%
Xg ---------- 100%
X = (254×100)/0,39
X = 65128,2 g/ mol <<<< molar mass
Two moles because one moles would be 6.02×10 23 atoms 2 moles would equal twice that number of atoms
Answer:
Energy of Movement.
Explanation:
Particles in a water wave exchange kinetic energy for potential energy When particles in water become part of a wave, they start to move up or down. This means that kinetic energy (energy of movement) has been transferred to them.
