The apple in my hand has three different forms of energy
that I can think of.
1). Thermal energy. I know that the apple's temperature is
not absolute zero, because it is not freezing my hand off.
Therefore it holds some heat energy.
2). Chemical energy. From previous experience, I know that
if I eat the apple, it gives me a boost and keeps the doctor away,
since my body is able to metabolize it, and extract nutrition from
its chemical energy.
3). Potential energy. Also from previous experience, I realize
that when I picked up the apple, I exerted force on it opposite to
the force of gravity. By doing work on it, I endowed it with increased
gravitational potential energy, which would immediately be obvious
if I dropped it to the ground, where it would either smash or dig a
little crater in the grass.
Ionic bond is formed due to the transfer of electrons from one atom to the other. In this bond, one atoms (the donor) loses (donates) one or more electron(s) to the other atom (the acceptor) in order for both to become stable.
Examining the choices we have, we will find that K needs to lose one electron while Br needs to gain one electron in order for both to be stable. Therefore, K loses one electron that is gained by Br.
Based on this, the bond in KBr is considered ionic.
The right choice is:
<span>K and Br </span>
The water molecules only oscillate up and down and not across the wave as water waves are transverse waves. Thus, the oscillations of the particles are perpendicular to the direction of wave propagation.
