When you drop iodine on a leaf you may observe a colour change of orange/brown to a blue/black complex.
This is because in the leaf there are starch molecules that form a blue/black complex with the starch molecules.
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Answer:
Double replacement reaction
Explanation:
Now, let us first write the reaction equation properly:
H₂SO₄ + 2KOH ⇒ K₂SO₄ + 2H₂O
The above reaction is a neutralization reaction between an acid and a base whose product gives salt and water only at most instances.
From here, we can observe that the species displaces on another in their ionic state. Hydrogen replaces potassium and water is produced. Potassium combines chemically with sulfate ions to give the salt of potassium.
Answer:
NO3-
Explanation:
Given the reaction equation;
Au(s) + 3NO3-(aq) + 6H+(aq)→Au3+(aq) + 3NO2(g) + 3H2O (l).
We can consider the oxidation states of species on the left and right hand sides of the reaction equation;
Au is in zero oxidation state on the left hand side and an oxidation state of +3 on the righthand side.
NO3- is in oxidation state of +5 on the righthand side and NO2 is in + 4 oxidation state.
H+ is in + 1 oxidation state on both the left and right hand sides of the reaction equation.
Since reduction has to do with a decrease in oxidation number, it follows that NO3- was reduced in the reaction.
Answer: A index fossil is any animal or plant preserved in the rock record of the earth that is characteristic of a particular span of geologic time or environment. A useful index fossil must be distinctive or easily recognizable, abundant, and have a wide geographic distribution and a short range through time.
Explanation:
Air is a insulator in normal conditions,but when heated up to high temperatures it becomes a conductor. <span />
