Answer: D. The elements have the same number of valence electrons
Explanation: The chemical reactivity of elements is governed by the valence electrons present in the element.
The elements present in the same group or vertical column have similar valence configurations and thus behave similarly in chemical reactions or have similar bonding properties.
For Example: Both fluorine and chlorine belong to same family or group and both have 7 electrons in their valence shell and thus accept single electron to attain noble gas configuration.
thus both would bond with a cation bearing a single positive charge.
Answer:
The object is dropped, we know the initial velocity is zero. Once the object has left contact with whatever held or threw it, the object is in free-fall. Under these circumstances, the motion is one-dimensional and has constant acceleration of magnitude g.
No so sure
Explanation:
Hope it helps
You are correct. Mountains are part of the lithosphere.
Ways carbon is added to the atmosphere is through the respiration of animals, the decay of plant matter, combustion of organic materials, and volcanic eruptions.
Answer:
The initial velocity of the snowball was 22.21 m/s
Explanation:
Since the collision is inelastic, only momentum is conserved. And since the snowball and the box move together after the collision, they have the same final velocity.
Let 
be the mass of the ball, and 
be its initial velocity; let 
be the mass of the box, and 
be its velocity; let 
be the final velocity after the collision, then according to the law of conservation of momentum:
.
From this we solve for , the initial velocity of the snowball:
now we plug in the numerical values 
, 
, 
, and 
to get:
The initial velocity of the snowball is 22.21 m/s.
<em>P.S: we did not take vectors into account because everything is moving in one direction—towards the west.</em>
