<span>The answer to this question would be: placement of electrons only
An atom with resonance structure or mesomerism has one or more different structure with different placement of the electron. The atom should have a same amount of electron but only differ in the electron position. This will result in a different Lewis structure model. In this structure, you can find </span>π electrons pair.<span>
</span>
Answer is (4).<span>
<em>
</em></span>
<span><em>Explanation:</em>
</span><span>
<span>The given mixture contains an </span>insoluble solid<span> <span>and an </span></span>aqueous solution of salt. <span>The insoluble solid is </span>sand. <span>
First </span><span>we have to separate </span>insoluble solid. <span>Sand can be separated by doing </span>filtration. When we filter the mixture sand can be seen as the residue on the filter paper.
<span>After filtering the mixture, we should collect the </span>filtrate. <span>Filtrate is the </span>salt solution. <span>By doing </span>evaporation <span>we can get the </span>solid salt. <span>
First </span>and second choices are wrong <span>because </span>after evaporating water filtration
cannot be done and salt and sand will be mixed together.<span>
Salt cannot be
filtered out because the salt is soluble and it is <span>in
aqueous medium. Hence, third choice is wrong</span></span></span>
Answer:
2 NO (g) → N2 (g) + O2 (g)
2 NOCl (g) → 2 NO (g) + Cl2 (g)
____________________________
2NOCl (g) ⟶ N2 (g) + O2 (g) + Cl2 (g)
ΔH = [90.3 kJ x 2 x -1] + [-38.6 kJ x -1 x 2] = -103.4 kJ
The ΔH for the reaction is -103.4 kJ
Answer:
TRUE.
Explanation:
Mass Number is the sum of protons and neutrons present in the nucleus of an atom. Isotopy is a phenonmenon that occurs when atoms of same elements have different mass number (Number of neutrons).
2H isotope has 1 proton and 1 neutron.
3H isotope has 1 proton and 2 neutrons.
This meeans 2H isotope has fewer neutrons when compared to the 3H isotope. The correct option is TRUE.
A homogeneous mixture is made up of multiple different substances. (You can see different parts)
Ex: Cereal in milk or ice in soda
A heterogeneous mixture is a mixture that is mixed well. ( you can’t see the different parts)
Ex: Rain or air
