The valence electrons are the parts of an atom that make interactions and make chemical bonds.
Every atom is made of three different components, a positively charged proton, neutrally charged neutron and negatively charged electron. The protons and the neutrons make up the atom's core and the electrons orbit around that core.
The electrons that orbit around the atom's core in its outer-most orbit (the one that is the furthest from the atom's core) can interact with electrons of other atoms, forming different kinds of chemical bonds.
If there is an exchange of the electrons (one atom donates its electrons to another atom), that results in forming of ions, then those two atoms can be linked in an ionic bond.
If an electron is shared between two atoms, then that bond is called a covalent bond.

3 0

3 years ago

Hot water enters a double-pipe counter-flow water-to-oil heat exchanger at 220°7 and leaves a 100°F. Oil enters at 70°F and leav

il63 [147K]

Answer:

Oil has the smaller heat capacity. The effectiveness of the heat exchanger is 0.80.

Explanation:

Part 1:

In order to know which fluid has the smaller heat capacity we need to consider the heat equation below:

Q = CΔT, where Q is the heat exchanged, C is the heat capacity and ΔT is the variation in temperature.

As the heat exchange is the same for both fluids, the smaller the temperature variation, the smaller the heat capacity.

Water: ΔT = 120 °F

Oil: ΔT = 80 °F

Therefore, oil is the fluid with the smallest heat capacity.

Part 2:

The effectiveness of a counter-flow heat exchanger is given by the equation bellow:

$E = \frac{Th1 - Th2}{Th1 - Tc1} \\$

Th1: initial temperature of the hot fluid

Th2: final temperature of the hot

Tc1: initial temperature of the cold fluid

$E = \frac{220 - 100}{220 - 70} \\E = 0.8$

7 0

3 years ago