Question: Predicting the shape of a molecule is relatively straight forward. A molecule's shape will always be determined by the number of electron pairs around the central atom. The number of electron pair corresponds to the number of atoms that are bound to the central atom of the molecule. For example, water contains two hydrogen atom bound to one atom of oxygen, giving the molecule a linear geometry.
Suppose that the model presented by student 1 is correct. Based on the information provided, what would be the bond angle in a molecule of perchlorate ion.
Answer: Suppose that the model presented by student 1 is correct The (perchlorate ion) will be a tetrahedral shape, O-Cl-O bond angle 109.5 due to four groups of bonding electrons and no lone pairs of electrons.
The x- and y-coordinates are 9142.57 m and -304.425 m
<u>Explanation:</u>
As the motion of the shell is in a plane (two dimensional space) and the acceleration is that due to gravity which is vertically downward, we resolve initial velocity of the shell 
in horizontal and vertical directions. If the initial velocity of the shell is making angle with the horizontal, the horizontal component of initial velocity will be
As the acceleration of the shell is vertical having no horizontal component, the shell may be considered to move horizontally with constant velocity of 
and hence the horizontal distance covered (or the x coordinate of the shell with point of projection as origin) is given by
For motion with constant acceleration, we know
Along the horizontal, x-axis, we might write this as
Measuring distances relative to the firing point means
we know that,
or,
By applying the values, we get,
The acceleration of gravity is vertically downward and is 
, hence the vertical distance covered (or y coordinate of the shell) is given by the second equation of motion
we know, 
and 
, so,
y = 11701.8 - 4.9(2450.25)= 11701.8 - 12006.225 = - 304.425 m
Friction can be bad by being too strong or too weak.
<span>Sometimes, when it is too strong, it decreases efficiency since some energy is wasted and turns to heat. Friction can also d</span><span>amage equipment/objects like when you slide it on the floor.
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When friction is too weak, like for instance when there is black ice- our center of gravity is displaced too quickly and we can fall. Likewise, if there is a lot of slush on the ground, cars can slip and slide.
Option D) A drop of mercury is both a pure substance and and element.
Happy to assist you !
Answer:
Inertia
F=ma
Action, reaction
All of the above
A heavy object requires more force to push than a lighter object.
