they're experts in iron metallurgy
The bantu was originated from the southern part of Africa ( round republic of Congo) , and has been the expert of utilizing iron among the ancient tribe
Mostly they use it for their Agricultural system ( such as their Irrigation system, for their agricultural tools, etc)
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Answer:
2-
Explanation:
The dichromate ion is the part of the compound that looks like: Cr2O7.
Our current compound is Ag2CrO7. The “2” on Ag indicates that there are two atoms of Ag in this compound, while the absence of a number on Cr2O7 indicates that there is only one atom of Cr2O7.
In order to maintain balance within the compound, the product of one of the ion’s charge with its atom amount must be equivalent to the product of the other ion’s charge with its atom amount. This is because the charges will ultimately add up to 0, which is the neutral substance we want.
Here, we know the “atom amount” of Ag is 2 and that its charge is 1+. So that’s 2 * 1 = 2. We also know that the “atom amount” of Cr2O7 is 1 and that its charge is x, for example. Then: x * 1 + 2 = 0. That means x = -2.
Thus, the charge on the dichromate ion is 2-.
Potato cells contains starch. When you add iodine solution into potato cells, you may observe that the brown color of iodine on the potato changes into a blue black color. This is because a starch/iodine complex is formed and it has a blue black color.
A hydrogen bond is formed by attraction between + and - charges on different water molecules.
Basically, it is the bond between two atoms that already participate in other chemical bonds. Hydrogen bonds may form between atoms within a molecule or between two separate molecules.
Answer: During a phase change, such as melting or boiling, the kinetic energy increases.
Explanation:
Kinetic energy is the energy obtained by the molecules of a substance due to their motion.
When phase change such as melting or boiling takes place then it means heat is absorbed by the substance. As a result, their molecules more even more rapidly from one place to another due to which more number of collisions take place.
Hence, a change in phase of substance occurs as kinetic energy increases in melting or boiling process.
Thus, we can conclude that during a phase change, such as melting or boiling, the kinetic energy increases.
