Answer = B = Neutrons and Mass Number
Isotopes are defined as those atoms which have same atomic number but different atomic masses.
Atomic mass is basically the number of protons and neutrons present in an atom.
Atomic number is the number of protons present in an atom.
So, in isotopes the number of protons are same but the number of neutrons vary due to which atomic masses also vary.
In given three isotopes, all have same number of protons but different number of neutrons.
i.e.
H-1 = 1 P + 0 N = 1 u (Proton)
H-2 = 1 P + 1 N = 2 u (Deuterium)
H-3 = 1 P + 2 N = 3 u (Tritium)
Hence, it is clear that the number after H shows a change in number of neutrons and mass number.
Answer:
CO2
Explanation:
CO2 or carbon dioxide is produced when iron is extracted from its ore. Carbon monoxide Co is used as reducing agent in iron extraction. In this reaction iron ore is reduced to iron and CO is oxidized to CO2 or carbon dioxide which is released in the process. There extraction of iron is redox reaction.
Just choice D.
If you find the number of atoms of each element, you will find that only choice D has the same amounts on each side of the equation.
<h2>Answer : Option B) Hydrogen</h2><h3>Explanation :</h3>
All fossil fuels contains hydrocarbons in it. Amongst the given options hydrogen is the correct answer. Except that it contains carbon in it. Hydrocarbons are those class of compounds which contains hydrogen and carbon as element in it.
They are considered to be good fuels because they naturally bring out complete combustion as they contain hydrogen and carbon in its compound form.
Endothermic reactions, on the other hand, absorb heat and/or light from their surroundings. For example, decomposition reactions are usually endothermic. In endothermic reactions, the products have more enthalpy than the reactants. Thus, an endothermic reaction is said to have a positive<span> enthalpy of reaction. This means that the energy required to break the bonds in the reactants is more than the energy released when new bonds form in the products; in other words, the reaction requires energy to proceed</span>