Barium has a 2+ charge as it is in group 2 in the periodic table and so it has two electrons in its outer shell and chloride has a -1 charge on its chloride ion. So we will need two of the chloride ions as we have a 2+ charge to match the amount of charge on one barium ion- forming barium ion
BaCI2
Answer:
<em>The correct option is A) The atom has changed over the years.</em>
Explanation:
Option A is not correct because an atom does not change. It remains the same always. The structure of an atom will always contain neutrons, protons and electrons.
Scientific theories tend to change over time as new information is brought up. Novel techniques lead to more advanced experiments and results. As a result, a scientific theory is subjected to change whenever evidence is found for a new theory which challenges the older one.
The atomic theory has changed many times due to novel scientific techniques and experiments.
Answer:
its shorter than a regular one
Explanation:
the only reason is simply because it is shorter
<span>Eukaryotic cells contain organelles that perform specialised functions.</span>
Answer:
Radiation
Explanation:
Thermal energy (heat) can be transferred between objects as long as there is a temperature difference between them. However, there needs to be some kind of medium transferring it. There are basically three ways in which the energy is transferred:
1. Conduction - transfer via the direct contact
2. Convection - transfer via the circular movement of fluids or air caused by hotter layers moving upward and colder downwards.
3. Radiation - transfer via the waves from the invisible spectrum of electromagnetic radiation ( ultra-violet, infra-red...)
Frequency is not a type of energy transfer, but a number of times something is occurring in one second. When we say that the frequency is 200Hz it means that something is happening at a rate of 200 times in a second. It's most often used in describing oscillations.