Answer: c. +4
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.




Here manganese is having an oxidation state of +4 called as cation and oxygen forms an anion with oxidation state of -2. Thus they combine and their oxidation states are exchanged to give
which written in simplest whole number ratios to give neutral 
The correct answer is - False.
The soils are part of most of the major cycles that take place on the Earth, mainly because they are in touch with the other spheres. The carbon dioxide, as well as the nitrogen and the sulfur cycles too, end up in the soil in more cases than not during their cycles. While some are formed in it and than released, like the sulfur, the carbon mostly gets in it though the roots of the plants, as well as the decomposing organisms, and the nitrogen ends up in the soil with the water.
The soil is one of the most important pieces in the cycles of most of the gases on Earth, and without it, some will not even be possible.
Out of the options, the best indicator is a color change since it is the only one that can't really be blamed on a physical change. you will eventually notice that during qualitative labs and some quantitative labs, usually the thing that you are looking for is either color change or the production of a precipitate to indicate the presence of a chemical reaction
Answer:
A coffee cup calorimeter is great for measuring heat flow in a solution, but it can't be used for reactions that involve gases since they would escape from the cup. The coffee cup calorimeter can't be used for high-temperature reactions, either, because they would melt the cup.
Answer:
Hyponym is the another name for hard water.
Explanation:
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