Are some chemicals safe while others are dangerous?

If i can still dissolve more sugar into the solution at a certain temperature what would i call that solution

Which set of characteristics best describes igneous rock? a) largest type of rock, made of organic matter, hardest type of rock b) least abundant type of rock, made of other rocks, made mostly of minerals c) found on all continents, contains wavy bands of stripes, contains fossils d) most abundant type in earth's crust, made of magma/lava, contains no fossils

‘which reaction would most likely require the use of an inert electrode?