<span>Two clear solutions are mixed and form a cloudy solution, A beaker of water becomes hot to touch upon adding detergent powder to it, Bubble formation on chalk added to acid. These are the evidence of a chemical reaction.</span>
The empirical formula for this would be FeS
The incorrect rule for assigning oxidation numbers is Hydrogen is usually –1.
Hydrogen is usually +1
<h3>What is oxidation number?</h3>
Oxidation numbers can be defined as that number which is assigned to an element in chemical reaction which represents the number of electrons lost or gained.
So therefore, the incorrect rule for assigning oxidation numbers is Hydrogen is usually –1.
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